Let me show you how easy slab pies are! Unlike traditional round pies, you can roll slab pies into any shape you want as long as it fits onto a sheet pan. This mixed berry slab pie uses a super flaky all butter pie crust and extra juicy berry filling. This is a very easy way to make and serve pie!
Summer pie season is here and that’s nothing to take lightly. Let’s make a free-form mixed berry slab pie with a flaky all-butter pie crust, juicy strawberries, fresh blackberries, and a squeeze of lemon to brighten up the whole dessert. I love slab pies because not only are they 100x easier than an actual pie, they’re essentially a giant pop-tart. If that doesn’t convince you, I’m not sure much else will. But I’ll give it a shot!
5 Reasons to Make Mixed Berry Slab Pie
- Slab pie is cut into bars so it’s easy to slice, serve, and eat.
- Eat with a fork or hands.
- Slab pie feeds a crowd.
- Easier to freeze leftover slab pie bars compared to traditional pie slices.
- No strict measurements for rolling out the dough.
Slab Pie Crust
Start this recipe with the same pie crust used for apple slab pie. This pie crust recipe is essentially my traditional all butter pie crust, but it yields 3 pie crusts instead of 2. (Slab pies are larger, so we need more pie dough.) You know I’m a cheerleader for the shortening and butter combination in pie crust, but I find this particular crust is fantastic for slab pie. It’s a wonderful balance of tender and crisp and browns beautifully in the oven.
The pie dough must chill for a couple hours, so it’s easiest to prepare the crust in advance. It can hang out in the refrigerator for a few days or in the freezer for 3 months. When you’re ready to make the mixed berry slab pie, don’t stress over rolling out the pie dough. Unlike traditional round pies, slab pies are no-fuss. Let the pie dough take on whatever shape, as long as it’s about 1/8-inch thick and can fit onto your baking pan.
Use Parchment Paper to Transfer
To make transferring the rolled out dough easier, roll it out on parchment paper. Pick up the parchment and place it on your baking sheet. I recommend a rimmed baking sheet, like a jelly roll pan, so any possible filling juices don’t go overboard. You could also roll the dough out on a silicone baking mat.
Low maintenance free-form pies will be your new favorite. You’ll love my berry cobbler, too!
Mixed Berry Filling
I love combining fruits to create unique pie fillings with varying textures. Juicy strawberries are the perfect match for the more sturdy blackberry. This duo yields a hot pink filling and if the giant pop-tart-ness doesn’t make you smile, this barbie pink filling will. Feel free to swap blueberries for the strawberries or blackberries.
There are some exceptions, but whenever you make pie filling, you need anywhere between 6-10 cups of fruit. For this slab pie, you need about 8 cups. Use half chopped strawberries and half blackberries. The blackberries I bought were extra large, so I chopped them in half.
My #1 Tip
Listen up! Berries are naturally juicy and will excrete even more juices after you mix the filling ingredients together. You will be tempted to pour the filling on the crust but DON’T DO THAT. There’s a lot of liquid at the bottom of the bowl— I measured about 1/3 cup— and that excess liquid leads to a soggy crust. Use a slotted spoon to transfer the filling to the pie crust, leaving excess liquid behind. Don’t worry, the baked pie filling will still be very juicy!
Finishing the Mixed Berry Slab Pie
Roll out the top pie crust in the same shape as the bottom. If desired, you can cut into strips to weave a lattice pie crust topping. If topping with a full pie crust, as I do in these photos, cut a few slits in the top crust so steam can escape. For a golden sheen, brush the top crust with egg wash. And because it’s fun to be EXTRA, add some sparkle with coarse sugar.
Serve the mixed berry slab pie warm or wait for the whole thing to cool down and slice into bars. (You’ll get neater slices if the pie has cooled down!) If you’re simply serving on plates, cut and serve warm with a scoop of vanilla ice cream and a dollop of whipped cream.
Celebrating summer pie season just got a whole lot easier and if you’re looking for more pie recipes, I’m your gal.
More Summer PiesPrint
Strawberry Blackberry Slab Pie
- Prep Time: 3 hours
- Cook Time: 50 minutes
- Total Time: 3 hours, 50 minutes
- Yield: 14-18 slices
- Category: Pie
- Method: Baking
- Cuisine: American
Simple strawberry blackberry slab pie recipe with an all butter flaky pie crust feeds a crowd! This is a free form summer pie assembled and baked on a baking sheet.
- 4 cups (500g) all-purpose flour (spoon & leveled)
- 1 and 1/2 teaspoons salt
- 1 teaspoon granulated sugar
- 1 and 3/4 cup (3.5 sticks; 400g) unsalted butter, very cold and cubed
- 3/4 cup (180ml) ice cold water
- egg wash: 1 large egg, lightly beaten with 1 Tablespoon (15ml) milk
- optional: coarse sugar for sprinkling on top
- 4 cups (650g) hulled and chopped fresh strawberries
- 4 cups (500g) halved fresh blackberries
- 1/2 cup (100g) granulated sugar
- 1/4 cup (28g) cornstarch
- 1 Tablespoon (15ml) lemon juice
- 1 teaspoon pure vanilla extract
- pinch salt
- Make the pie crust: Mix the flour, salt, and sugar together in a large bowl. Add the butter. Using a pastry cutter, a food processor, or two forks, cut the butter into the mixture until you have pea-size crumbles with a few larger crumbs of fat. (I prefer a pastry cutter for control, ease, and so it’s not accidentally over-mixed.) Drizzle the cold water in, 1 Tablespoon (15ml) at a time, and stir after every Tablespoon added. Do not add any more water than you need to. Stop adding water when the dough begins to form large clumps. I always use about 3/4 cup (180ml) water. Transfer the pie dough to a floured work surface. Using floured hands, fold the dough into itself until the flour is fully incorporated into the butter pieces. The dough should come together easily and should not feel overly sticky. Form dough into a ball. Divide dough in half. Flatten each half into 1-inch thick discs using your hands. Wrap each tightly in plastic wrap. Refrigerate for at least 2 hours (and up to 5 days) or freeze for up to 3 months. Thaw overnight in the fridge before using.
- Make the filling: Gently mix all of the filling ingredients together in a large bowl. Set aside.
- Preheat oven to 375°F (190°C).
- Roll out the chilled pie crust: Remove 1 disc of pie dough from the refrigerator. Keep the other in the refrigerator as you work. I highly suggest rolling the dough out onto a piece of parchment paper or silicone baking mat fitted to your baking sheet. This way you can lift the entire piece of parchment/silicone baking mat off the counter (with the rolled out dough on top) and place on the baking sheet. Roll the dough out into a rectangle or oval shape. I find anywhere around a 10×16-inch size is great, though I’ve stretched it to a 13×18-inch size. Anywhere around this measurement will work. Dough should be about 1/8-inch thick. Make sure to turn the dough about a quarter turn after every few rolls. Carefully place the dough (with parchment/silicone baking mat) onto a large rimmed baking sheet.
- Spoon filling evenly on top of crust, leaving any excess liquid in the bowl. Leave a bare 1-inch border around the edges.
- Roll out the 2nd pie dough disc in the same-ish shape as the 1st. (If desired, you can cut into strips to weave a lattice on top.) Drape over filling, then use your hands to seal the top and bottom crusts together around the edges. Flute the edges or crimp with a fork. Cut slits into the top of the crust, then brush with a thin coating of egg wash. Sprinkle with coarse sugar, if desired.
- Bake the slab pie for about 45-55 minutes until the crust is golden brown and you can see the filling bubbling. Remove from the oven and, if serving as hand-held bars, allow to cool completely in the pan set on a wire rack. If serving on plates, allow to cool for at least 45 minutes in the pan set on a wire rack. This pie is fantastic served a little warm with vanilla ice cream or at room temperature (or as cold leftovers, yum!).
- Cover leftovers tightly and store in the refrigerator for up to 3-4 days.
- Make Ahead Instructions: The pie crust dough can be made ahead of time and stored in the refrigerator for up to 5 days or in the freezer for up to 3 months. Thaw overnight in the refrigerator before using. Baked whole pie or sliced pie bars freeze well for up to 3 months. Thaw overnight in the refrigerator and allow to come to room temperature before serving.
- Special Tools: Glass Mixing Bowls | Pastel Measuring Cups | Pastry Cutter | Pastry Brush | Baking Sheet | Rolling Pin
- Berries: Avoid using frozen berries. Pie filling does not set when using frozen or frozen thawed berries. You’ll need about 1 and 1/2 pounds of both whole strawberries and blackberries. Feel free to substitute either berry with blueberries.
Keywords: strawberry blackberry slab pie
Reader Comments & Reviews
Should I use flour or not when rolling the crust out?
Yes, a light dusting of flour!
This was ultimately delish but I did find that I had way too much filling for the crust. I only used about half to two-thirds, and even with the smaller amount, it leaked out of the crust. Wonder what I might have done wrong there?
Hi Dana! Did you roll out the dough to the proper size and spoon filling on top of crust, leaving any excess liquid in the bowl? Glad you still enjoyed it!
This looks delicious and easy enough for me to try. I’m planning to make this for the 4th of July and was thinking of using pie crust cut out in the shape of stars on top. Do I need to bake this any differently if I cover in stars instead of a solid pie crust on top?
Hi Lisa, sounds fun! You can follow the baking times as is with the star cut outs. Let us know how it goes!
I was hoping to make a strawberry rhubarb pie, but rhubarb being basically nonexistent around here, I’ve had to shift gears. I managed to find a handful of tiny rhubarb stalks at a farmers market, so I’m thinking of using the strawberry/blackberry combo here and then sprinkling in the little bit of rhubarb I have for a hint of tart throughout. Do you think those flavors would work together? Also, I was wondering how you might adjust amounts to make a pie that goes completely edge to edge on a standard jelly roll pan, vs how you’ve sized it in these photos. Would it stretch or would I need to bump up the amount of crust and filling a bit?
Hi Krystal, You can see how we used the same amount of crust to fill the whole pan in this apple slab pie. You may wish to use a bit more filling but the addition of rhubarb would be delicious. Let us know if you give it a try!
I made this for a fourth of July party and it turned out great! It was a little hard to roll the crust though. I think next time I’ll chill the dough as flatter rectangles. I used fresh picked sour cherries and blueberries. Other recipes I looked at did not seem to have enough dough to fill a large bar pan, this one did!
big fan of a lot of your recipes; I had a wonderful time with this recipe. The filling was enough for three store-bought pie crusts I fashioned into slabs.
I’m here to ask: How would you recommend re-heating this? (Both as a cut, whole pie and as individual pieces.)
Hi Rikki, you could either microwave individual pieces or reheat the pie in the oven (same temperature) until warmed to your liking. So glad this one was a hit for you!
I’ve used your all butter pie crust recipe several times and love it. But on this one you got to 4 cups flour with 1 teaspoon sugar instead of 2.5 cups flour with 2 teaspoons sugar. It seems odd to reduce the sugar for more flour. Thank you for your help.
Hi LouAnn! You can slightly increase the sugar in this pie crust. (1 Tablespoon would be great.) I never used to add sugar to pie crust so I started out slowly. Now when I make this crust for slab pie (which produces about 3 9-inch pie crusts), I add a little more than 1 teaspoon. Fine either way.
Sally, help! I might have overworked the crust or not baked long enough. It is just a bit heavy. Used fresh strawberries that we picked yesterday that are sweet as can be. Strawberry filling still tasted sweet before it went onto the crust. What leaked out was super sweet. But what we ended up with was rather tart. What might I do differently next time? And do you think a glaze now might sweeten it up? Thanks!
Hi Melissa, If you found it a little too tart for your taste, you can definitely cut back on the lemon next time. Thank you for trying this recipe!
I took my pie crust out of the fridge and it seems too hard to roll. What did I do wrong?
Hi Nelly! If the dough is just too hard right out of the refrigerator, let it sit at room temperature for 10 minutes. It will still be cold, but even a few minutes at room temperature will help soften it up.
Whats wrong with frozen berries?
Hi Dave! Frozen berries release too much liquid that will keep the pie filling from setting up. It’s best to stick with fresh berries for this recipe.
First time pie maker here and it turned out great! Big thumbs from my husband and toddler children. I spooned out the berries and it was still verrrrryyyy juicy. But the crust wasn’t soggy; I was so surprised. Thank you for the clear and thorough instructions. Delicious!
Hi Sally, please let me know if I can use canned cherry filling, as I would love to make this with cherries but unfortunatelly have’nt been able to find sweet cherries yet.
I have already made your recipe once as it is, and it worked out GREAT!!!
Hi Katharina! You can use canned cherry filling for the entire filling if desired! You could leave out the other berries and filling ingredients.
Dear Sally, I made the pie with a combination of canned cherry filling and some fresh I found at the market and it worked out PERFECT!!!!!! Thank you so much for another great recipe, with metric measures,and especially for alway replying on comments!
I’m doing a dessert bar for my daughter’s wedding this summer (what did I get myself into??) She loves strawberry-rhubarb pie. If I made it as a slab pie, would this freeze well that I could make it a couple weeks ahead of time? If so, what do you recommend for thawing and then serving? Would it need to be stored in refrigerator once removed from freezer prior to the reception?
Hi Jenny! You can freeze the baked pie for up to 3 months. I recommend thawing at room temperature or in the refrigerator. It can sit at room temperature for about 1 day. Pie tastes best served at room temperature.
Here’s is a quick tip for anyone looking to not waste the deliciousness of the extra liquid that remains once you have strained the berries onto the pie crust. I add some more berries and then cook it (gently bring to a boil) on the stove top and create a sauce that I then put over top of the ice cream I serve with the squares. Waste not want not is what I was always told 😉
Can you just use frozen pie crust???
You can use store-bought frozen pie crust, yes!
Can I replace the blackberries with raspberries?
Yes, you sure can!