Blueberry Slab Pie
intro
Buttery flaky double crust packed with jammy, sweet-tart fresh blueberry filling, cut into easy shareable squares perfect for summer group gatherings and potlucks.
Ingredients
Steps
Make flaky pie crust
In a large food processor, combine 420g (3 ½ cups) all-purpose flour, 25g (2 tbsp) granulated sugar, and 1 tsp fine sea salt. Add 340g (1 ½ cups) cold 1cm-cubed unsalted butter, pulse 8-10 times until butter pieces are the size of small peas. Slowly drizzle in 120ml (½ cup) ice water, pulsing only 2-3 times just until the dough begins to clump together (do not overmix, as this creates tough crust). Split the dough into two unequal portions (2/3 for the bottom crust, 1/3 for the top), flatten into 2cm-thick rectangles, wrap tightly in plastic wrap, and chill in the refrigerator for 30 minutes.
Mix blueberry filling
While the dough chills, make the filling: in a large mixing bowl, toss 900g (6 cups) rinsed, thoroughly patted-dry fresh blueberries with 150g (¾ cup) granulated sugar, 45g (3 tbsp) cornstarch, 1 tbsp fresh lemon zest, and 30ml (2 tbsp) fresh lemon juice until every berry is evenly coated. Let the mixture rest for 10 minutes at room temperature, stirring once after 5 minutes, to let sugar dissolve and juices release slightly.
Roll bottom crust layer
Preheat your oven to 200°C (400°F) with a rack positioned in the middle. Remove the larger chilled dough portion from the refrigerator, roll it on a lightly floured work surface to a 33cm x 40cm (13in x 16in) rectangle that is 3mm thick. Gently lift and drape the rolled dough into a 23cm x 33cm (9in x 13in) rimmed baking sheet, pressing it firmly against the pan bottom and up the sides, trimming any excess overhang to 2cm beyond the pan edge.
Assemble the slab pie
Pour the rested blueberry filling and all its accumulated juices evenly over the bottom crust, spreading into a smooth, level layer. Roll the smaller chilled dough portion to a 28cm x 38cm (11in x 15in) rectangle, 3mm thick. Drape this top crust over the filling, then fold the excess bottom crust over the top crust edge and crimp firmly with your fingertips to create a tight seal. Cut 5 evenly spaced 2cm slits across the top crust to allow steam to escape during baking.
Bake until bubbly golden
Brush the entire top crust and crimped edge with the beaten 50g large egg, then sprinkle evenly with 1 tbsp coarse sanding sugar for a crunchy, shiny top. Bake for 40-45 minutes at 200°C (400°F), until the crust is deep golden brown and blueberry juice is actively bubbling through the steam slits. If the crust edges darken too quickly after 25 minutes of baking, cover them loosely with thin strips of aluminum foil to prevent burning.
Cool and slice squares
Remove the baked pie from the oven and transfer the entire pan to a wire cooling rack. Let the pie cool completely at room temperature for 2 full hours to allow the filling to set firmly. Once cooled, slice into 12 even 7cm (3in) squares and serve at room temperature or slightly warmed.
Tips
2.Always pat rinsed blueberries completely dry before mixing into the filling; excess water on the berries will create a runny filling and soggy bottom crust.
3.Do not skip the full 2-hour cooling period after baking; slicing the pie warm will cause the unset filling to run out, leading to messy slices and soggy crust.
OMG this blueberry slab pie was an absolute game changer for our 4th of July cookout! I doubled the recipe to feed 15 people and there was barely a crumb left. The crust was flaky AF and the blueberry filling wasn’t too sweet, which everyone raved about. 10/10 will make again for our next neighborhood potluck!
Super tasty, but I will say the crust was a little trickier to roll out to the full sheet pan size than I expected! I ended up patching a couple of spots and it still turned out great, just don’t stress if your dough isn’t perfectly even. My kids loved it so much they asked for seconds before they finished their dinner, lmao.
Made this for our Sunday family dinner and it was a huge hit! I added a little lemon zest to the filling like I do with all my blueberry pies and it brightened the flavor up so much. Perfect for serving a crowd without having to mess with slicing individual pie slices, love the slab format!
Took me a little longer than the listed 1hr10 cook time because my oven runs a little cool, so I added 10 extra minutes and it came out perfect. The crumb topping? *Chef’s kiss* I was worried slab pie would be messy to serve but it sliced cleanly even straight out of the pan. SO good.
I made this for a work potluck yesterday and so many people asked for the recipe! The only change I made was using a mix of blueberries and a handful of raspberries I had leftover in the fridge, and it was chef’s kiss. Don’t skip the egg wash on the crust edges, it gets so perfectly golden and crispy.
This recipe was so easy to follow even as a pretty casual baker! Quick question though—has anyone tried making this gluten free? My sister has celiac and I want to make it for her birthday gathering next month. I usually use a GF all purpose flour blend but wasn’t sure if the crust would roll out okay for the sheet pan size.
Made this for our beach cookout last weekend and it held up so good even in the Florida heat! I kept it in the cooler until we were ready to serve and it was perfect, no soggy crust, no runny filling. All my friends were begging for the recipe, even the people who say they “don’t like fruit pie”. Win in my book!
I was nervous to try a slab pie because I’m terrible at making pie crust, but the instructions for the crust here were so straightforward! It came out flaky and buttery, no tough crust at all. I even made a little lattice design on top with extra dough and it looked so fancy, my husband thought I bought it from a local bakery.