These frosted sugar cookie bars are soft, chewy, and topped with creamy vanilla buttercream. And sprinkles… of course!
I’ve been dying to make sugar cookie bars with light ‘n sweet frosting for ages now! In all their soft-baked, mile high frosting, sprinkles-to-the-max goodness… I can honestly say that these charming little treats were well worth the wait. I mean, just look at ’em.
The frosting is as thick as the cookie!! Have mercy.
Today’s recipe is as soft as my favorite chocolate chip cookies and peanut butter cookies, as chewy as my favorite candy bar blondies, and as sprinkly as my entire cookbook. You’ll find sprinkles in the cookie bar base AND on top of the frosting. Is there such a thing as too many sprinkles? Because I’m pretty sure we test those limits here on my blog.
To make the frosted sugar cookie bars ultra soft, I add a touch of cornstarch. Trust me on this! Think about it: often used as a thickening agent, cornstarch gives your gravy, pie fillings, soups, and glazes a more bodied and full texture. The same goes for your cookie dough—cornstarch will help your dough remain soft, thick, and puffy during the baking process. The small 1.5 teaspoons used is certainly a heavy lifter in this recipe!
To make the cookie bars ultra chewy, I add an extra egg yolk. I do this with a few of my cookie recipes because that little extra yolk adds so much moisture, tenderness, and chew to the cookie. And it does the same thing to the sugar cookie bar base in this recipe. You’re going to love their rich, tender texture.
What’s great about this recipe is that you don’t have to chill the cookie dough. Just press the dough into the pan and bake right away. Bake the bars in a square baking pan—an 8-inch square pan or 9-inch square pan is fine. Only about 25 minutes. You want to slightly underbake the cookie bars in order to avoid the edges from getting too crispy and brown.
Allow the bars to cool completely before frosting. This will feel like an eternity.
If you’re the kind of person who eats cake just for the frosting, you’re going to love this recipe. And we would also get along very well.
You’ll use my basic vanilla frosting recipe for these bars. Classic, fluffy, and simple. I like to add a touch of salt to cut the frosting’s sweetness. With the sweet sugar cookie bar underneath, that tiny pinch of salt will help tame a sugar rush. Don’t get me wrong, these bars are still plenty sweet! Don’t bring them to your dentist.
And as you can see, the frosting layer is just as thick as the cookie layer. In some spots, even thicker—those were the best bites. The frosting recipe as written makes a ton, so don’t be afraid to frost the bars with a heavy hand.
Don’t want that much frosting? It’s ok, I forgive you. Feel free to halve the frosting recipe.
Ordinary ingredients can produce extraordinary desserts. Only simple, straightforward items used in this recipe and yet, the results will blow your mind!Print
Frosted Sugar Cookie Bars
- Prep Time: 25 minutes
- Cook Time: 25 minutes
- Total Time: 1 hour, 30 minutes
- Yield: 16 bars
- Category: Bars
- Method: Baking
- Cuisine: American
These frosted sugar cookie bars are soft, chewy, and topped with creamy vanilla buttercream. And sprinkles… of course!
- 1/2 cup (115g) unsalted butter, softened to room temperature
- 3/4 cup (150g) granulated sugar
- 1 large egg + 1 egg yolk*
- 2 teaspoons pure vanilla extract
- 1 and 1/2 cups (188g) all-purpose flour (spooned & leveled)
- 1/4 teaspoon salt
- 1 teaspoon baking powder
- 1/2 teaspoon baking soda
- 1 and 1/2 teaspoons cornstarch
- 1/2 cup (80g) rainbow sprinkles (not nonpareils)*
- 3/4 cup (170g) unsalted butter, softened to room temperature
- 2 and 1/4 cups (270g) confectioners’ sugar
- 3 Tablespoons (45ml) heavy cream or half-and-half*
- 1 teaspoon pure vanilla extract
- salt, to taste
- optional: food coloring (I used 1 drop red for this pink frosting) and extra sprinkles for decorating on top
- Make the bars: Preheat oven to 350°F (177°C). Line an 8-inch square pan or 9-inch square pan with aluminum foil, making sure to leave enough overhang on the sides. Set aside.
- In a large bowl using a handheld mixer or stand mixer fitted with a paddle attachment, cream the softened butter for about 1 minute on medium speed. Get it nice and smooth, then add the sugar on medium speed until fluffy and light in color. Beat in egg, egg yolk, and vanilla. Scrape down the sides as needed.
- In a medium bowl, whisk together the flour, salt, baking powder, baking soda, and cornstarch. With the mixer running on low speed, slowly add the dry ingredients to the wet ingredients in 3 different parts. The dough is quite thick. Once combined, gently fold in 1/2 cup sprinkles using a rubber spatula (or by mixing on low speed).
- Press the cookie dough evenly into the prepared baking pan. Bake for 25-26 minutes or until very lightly browned on top. You want the cookie bars to be extra soft, so careful not to overbake. Allow the bars to cool completely on a wire rack at room temperature before frosting. The center will slightly sink—that’s normal.
- Make the frosting: If you don’t want a super thick layer of frosting as pictured, halve the frosting recipe. With a handheld or stand mixer fitted with a paddle attachment, beat the butter on medium speed until creamy, about 2 minutes. Add confectioners’ sugar, cream, and vanilla extract with the mixer running on low. Increase to high speed and beat for 3 full minutes. Add more confectioners’ sugar if frosting is too thin or more cream if frosting is too thick. Add a pinch of salt if frosting is too sweet. I usually add anywhere between 1/8 – 1/4 teaspoon of salt. Beat in food coloring, if using.
- Remove cooled bars from the baking pan using the aluminum foil overhang on the sides. Frost the bars with a thick layer of frosting and decorate with extra sprinkles if desired. Cut into squares. Use a very sharp knife and wipe off with a paper towel between each cut to make neat, even cuts. Store bars in an airtight container at room temperature for up to 2 days and in the refrigerator up to 5.
- Make Ahead & Freezing Instructions: You can make these bars and the frosting 1 day in advance– store the bars, covered, at room temperature overnight and store the frosting, covered, in the refrigerator. Frost before cutting and serving. You can also freeze the unfrosted bars for up to 3 months. Thaw overnight in the refrigerator, frost, cut, and serve.
- Special Tools (affiliate links): 8-Inch Square Pan or 9-Inch Square Pan | Electric Mixer (Handheld or Stand) | Glass Mixing Bowl | Whisk | Silicone Spatula
- Eggs: Room temperature egg and egg yolk preferred. To bring the egg to room temperature quickly, place in a warm glass of water for about 10 minutes as you get the other ingredients ready. Or just set out when you set out the butter to soften 1 hour ahead of time.
- Sprinkles: Use regular sprinkles (aka “jimmies”) in the cookie bar base. Nonpareils (the little balls) will bleed their color and turn the sugar cookie dough green/purple/brown. I order my sprinkles in bulk here.
- Cream: Cream or half-and-half is preferred for creamiest, fluffiest frosting. Keeping that in mind, milk would be an OK substitute if you do not have either on hand.
- Larger Batch: You can double this recipe and bake in a 9×13 pan; the bake time is about 35 minutes.
Keywords: frosted sugar cookie bars, sugar cookie bars
Reader Comments & Reviews
Delicious! I doubled the recipe and baked in a 9×13 pan for my daughter’s easter party. The middle did sink compared to some high outer edges so I just trimmed the edges off for my husband and I to snack on and frosted the middle to cut into bars. I did pink buttercream but did not double that, did just the amount per the original recipe and it was plenty especially with just frosting the center. Added blue and yellow sugar and they were so cute! : )
I doubled it per your instructions for a 9×13 even though I knew a 9×13 is 1.8 times a 9×9. The bars were too thick. Even so, most people liked them.
I do have a question. How many ounces are in the 1/2 cup jimmies you call for in the base? Thank you. I really love your recipes and I will make this one again.
Hi K, We are happy you enjoyed this recipe! 80g is about 2.8 ounces. Keep in mind every brand of jimmies may have slightly different weights.
Very good! I made these with the half recipe of frosting, and my kids and I all really enjoyed them!
I made these at Christmas with green frosting and cut them into little triangles so they looked like Christmas trees! They were a HUGE hit and I think I’ve made them three times since then! The frosting to cookie ratio is impeccable!! And I have celiac disease, so I substitute the flour with King Arthur’s Gluten Free measure-for-measure flour and no one is able to tell the difference! These will be a staple in my family for a looooong time!
I made these for Valentine’s Day, and I do recommend them. I halved the frosting, and it was still plenty. The middle sank A LOT, which made for some small center pieces. I am wondering if there is a way mound the center so they even out when they cool. The taste is lovely, and the frosted bars are very pretty.
They look amazing! Is there an egg free version or substitute possible?
I love these cookies so much! They are easy to make and tastes wonderful! I like to substitute Lorann Princess emulsion for the vanilla and it makes them even more divine!
These tasted amazing and had great flavor and were a big hit. My only complaint is, that mine turned out more thickness of a cake. Still super soft, but just thick
I want to make these for my grandson who loves sprinkles, but I find the directions for making in advance a bit confusing. If I do make 2-3 days before serving, they will keep frosted and covered tightly in the refrigerator? Or is it still necessary to bake 2-3 days ahead,, keep covered in refrigerator but wait to frost them until it’s being served? I know he’s going to love these! Thank you.
Hi Fran, the completed bars + frosting will stay in refrigerator for up to 5 days, so you can take that approach if preferred. You can certainly make them separately and store per the recipe notes, and top the bars before serving. Hope your grandson loves these bars!
I tried these because the dough didn’t need chilling and they take up less space then traditional drop sugar cookies. Half the frosting was perfect! If making a 9″ pan, definitely check for doneness sooner then the suggested 25 minutes.
I like the recipe but it sinks so much in the middle every time I make it? So when I go to ice them, the outer edge gets less and the middle gets a ton. You said some sinking is normal but mine is always a lot. 🙁
Hi Lisa, does the cookie seem overly wet in the middle? A little sinking is normal as you mention, but if it’s sinking too much, it could be possible that it’s not quite baked through. An extra minute or two in the oven should help.
I like the recipe but would make a couple modifications. I baked in an 8×8 pan for for 15 minutes and the bars turned out drier than I prefer. I also added a bit of almond extract into the frosting. Thank you for sharing!
Sally, These have become our favorite celebration cookie bar! Love the tender cookie base & love, love the buttercream frosting! Thank you!
What does the baking soda react with in this recipe? I assume 2 tsp or 1 1/2 tsp of baking powder would suffice as well?
Can these be made with a chocolate frosting, if so do you have a recipe?
You could also make two pans of cookies, then sandwich the frosting between them. For better presentation, face the two bottom side of the cookie layers toward each other, then lightly wrap the cookies in plastic wrap, then bubble wrap to keep them from shifting around too much
Can you frreze these bars frosted or should you freeze then thaw and frost?
Hi Ellen, For the best results freeze the unfrosted bars for up to 3 months. Thaw overnight in the refrigerator, frost, cut, and serve.
I’ve made these cookies before with my middle school students for a special cooking class, and they turned out fantastically great!
Now, I’m wanting to make these and ship them to my brother’s family for Christmas. Do you think these will hold up in the mail? Will they go bad in transit?
Hi Gerri, we’re thrilled to hear you enjoyed the sugar cookie bars so much! With the amount of frosting on top, they might be a bit messy to send. You could try swapping some of the butter in the frosting with shortening for more of a “crusting” buttercream, and send them in a single layer to prevent them from getting smushed. Let us know what you try!
Do you sift the powdered sugar before or after weighing?
Hi Chelsea, We don’t sift the confectioner’s sugar in this frosting but you certainly can. If the recipe doesn’t say, then you should sift after measuring.
If a recipe calls for “1 cup of flour, sifted” — measure the flour, then sift it. If a recipe calls for “1 cup of sifted flour” — sift the flour then measure. It all depends where the word “sifted” is in the ingredient wording. If “sifted” is before the ingredient name, sift before measuring. If “sifted” is after the ingredient name, sift after measuring. I hope this helps!
I’d like to make these for my daughter’s upcoming school carnival. I think they would look great Halloween themed. However, to Covid each bar has to be individually packaged in a ziplock. Do you think the buttercream frosting will harden enough for this? Any tips? TIA!
Hi Nicole, it won’t completely harden, but should harden enough that wrapping individually would be just fine. If you want, you can swap out some of the butter for shortening for a “crustier” buttercream. Hope they’re a hit!
Thank you, Lexi! Do you have a recipe for a buttercream that has shortening? I’m not sure how much to add. 🙂
My go to recipe for when I need to bring a dessert! I follow the recipe exactly and they’re perfect everytime!
excellent recipe! This was my first time making the bars and they turned out great. I didn’t have a square pan so I baked mine in an 11×7 and wound up baking them about 17 minutes. I like the almond flavoring in Sally’s other sugar cookie recipe so I cut the vanilla to 1 tsp and added 1/2 tsp almond extract to the cookie. I loved the flavor and texture of the cookie! The frosting was excellent, I used the full recipe and the whole family loved it. Will put this one in rotation. It was as easy to make as boxed brownies too!!
I doubled the recipe for my 9×13 pan and took them out at around the 30 minute mark- they actually looked plenty brown at 25 minutes. They do puff up like a cake, which is a little weird and was slightly alarming to me, but they go back down and taste pretty good.
I also sacrificed a cookie to see what happens if they’re frozen with the frosting- I use another cookie bar recipe that has a heavier cream cheese-based frosting and have successfully frozen those cookies frosted without issue for over six months, and wondered what this recipe’s lighter frosting would do. Just wrapped tightly in plastic and tossed in the freezer until solid, then thawed at room temp, it tasted perfect. Heck yeah! That’s another keeper.
these are so delicious! i’m making them again today for our 4th of july dinner, due to popular request.
the frosting is to die for, and the bars themselves are so yummy. thanks!!!!