Skinny Peanut Butter Swirl Brownies

A healthier option for peanut butter brownies. Super fudgy brownies made without white flour, butter or oil!

Skinny Peanut Butter Swirl Brownies! Gluten-free, made with whole-grain oats, no flour, no butter, no oil, and with a ton of sugar substitute suggestions! These are so fudgy, you won't miss the unhealthy ingredients!

Oh my word.  Do I have a treat for you guys today.

I honestly think I am dreaming because today not only am I bringing you the fudgiest, richest, softest, chewiest brownie I have EVER eaten,  I am bringing you a fudgy, rich, soft, chewy, and SKINNY brownie swirled with my one true love (sorry, Kevin): peanut butter.

Skinny & brownie in the same title is a tad ironic, but I am telling you friends… you are not dreaming.

As I begin to train for the Baltimore half marathon coming up in 4 months (anyone else out there running that?  let’s be friends), I knew I needed a little treat to put some pep into my running step.  Preferably something tasting sinfully chocolatey and smothered in peanut butter because, well… why not.

Most brownie recipes call for loads of butter or oil, white flour, excessive amounts of sugar, and 3+ eggs.  Hence, their wonderfully decadent + rich taste.  My skinny brownies, however, combine much healthier alternatives, making these brownies good enough to call breakfast!  (Yes, I had one for breakfast this morning before my run… thankyouverymuch!) Instead of clogging the brownies with butter and oil, which would inevitably slow me down and have me feeling lethargic, I loaded the brownie batter with low fat vanilla greek yogurt.  It gives these brownies that unbelievable moist and fudgy taste that I love in my favorite not-so-healthy chocolate brownies.

In fact, these brownies are so rich and fudgy that someone even told me they tasted like straight up chocolate/peanut butter FUDGE! I can’t even believe there is no oil, butter, or flour these!

Skinny Peanut Butter Swirl Brownies! Gluten-free, made with whole-grain oats, no flour, no butter, no oil, and with a ton of sugar substitute suggestions! These are so fudgy, you won't miss the unhealthy ingredients!

In addition to the low fat greek yogurt, I used fiber-rich, whole grain oats instead of white flour – whole grain carbs are a perfect way to start your day and/or fuel a workout!  The recipe only calls for 1/2 cup of oats which are ground up into a flour.  A brownie’s fudginess directly relates to the amount of flour in the recipe.  And with only 1/2 cup of ground up oats in the entire recipe, you can imagine the density and fudginess of these babies!

My recipe has white sugar, but you could easily use 1/2 cup of honey instead. Some readers have even used Truvia, a mix of 1/2 cup brown sugar and 1/4 cup honey, or even 1/2 cup sugar and 1/2 cup dates instead of the 1 cup of white sugar. No matter how you chose to sweeten it, taste the batter to make sure it is sweet enough.

And to put these brownies completely over the top, I threw in a THICK peanut butter swirl because I firmly believe that there is nothing better in this world than chocolate and peanut butter.  Peanut butter is full of healthy fats and protein… perfect for shiny hair, glowing skin, and keeps your muscles workin’!

You will not believe these fudgy peanut butter swirl brownies are lightened-up! Learn how to make them at

So today, here is your recipe for what may the BEST brownie you’ll ever taste.  AND a brownie you can actually feel good about eating!

See more of my healthy recipes.


Skinny Peanut Butter Swirl Brownies

Makes 12-16 brownies. Full nutrition information available by visiting a calorie counting website and plugging in the ingredients. Make sure oats are certified gluten free if gluten intolerant.


  • 3/4 cup (185 grams) creamy peanut butter (do not use natural, runny peanut butter or powdered "peanut butter")
  • 6 oz. low fat or fat free vanilla greek yogurt
  • 1/4 cup (60 ml) skim milk (or almond milk)
  • 1 large egg (or 2 egg whites)
  • 1/4 teaspoon salt
  • 1 teaspoon baking powder
  • 1 cup (200 grams) granulated sugar (see note above in post about substitutions)
  • 1/2 cup (42 grams) unsweetened cocoa powder
  • 1/2 cup (40 grams) old-fashioned rolled oats


  1. Preheat oven to 350F. Spray a 8×8 inch pan with non-stick cooking spray. Set aside.
  2. Place all of the ingredients except for the peanut butter into a blender or food processor. (Yes, a blender!) For easier blending, place the liquid ingredients into the blender first. Blend until mix is smooth and oats are ground up. You will have to stop the blender and scrape down the sides a few times.
  3. Pour batter into prepared baking dish. Batter will be thin. Microwave peanut butter for about 30 seconds. Drop melted peanut butter by spoonfuls onto the batter, swirling gently with a knife to create a marbled effect. (Try not to overmix!)
  4. Bake for 20-25 minutes or until brownies begin to pull away from the sides of the pan. Brownies will be extra fudgy, so be sure to wait until COMPLETELY cooled - I stuck mine in the refrigerator for 2 hours, which allowed them to be cut very easily. Cut into squares and enjoy!  Brownies stay fresh at room temperature for 2 days, and then can be stored in the refrigerator for up to 5 days after that. Brownies freeze well up to 2-3 months.

adapted from Dashing Dish

Recipe Notes:

adapted from Dashing Dish

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Skinny AND tasty is my specialty 😉


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  1. Hi Sally – making these today! Can I substitute the oats with coconut flour?!

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