This slab pie is made on a quarter sheet pan (half the size of the traditional half sheet). If making on a half sheet, double the recipe. The pie crust uses oats, regular flour, and wheat flour to yield a super sturdy yet flaky crust. I like my crust thin. This recipe yields just enough. If you prefer a thicker crust, scale up the crust recipe. As usual, I like to keep things just sweet enough these days. With that said, this recipe was tested using sweet strawberries. Taste your strawberries first, trust your gut, and add a bit more sugar to the filling if needed.
Multigrain Pie Crust:
- 3/4 c. all purpose unbleached flour
- 1/2 c. oat flour (see notes)
- 1/2 c. wheat pastry flour
- 2 tsp. pure cane sugar
- 1/2 tsp. kosher salt
- alotta unsalted butter (1 1/2 sticks or 12 tbsp), chilled
- 1/2 c. icy cold water, plus more if needed
- 2 lb. (about 5 cups) Driscoll’s Strawberries, diced
- heaping 1/2 c. pure cane sugar
- 1/4 c. non-GMO cornstarch
- splash of pure vanilla extract
- pinch of kosher salt
- 1 large egg, whisked
- sprinkle of turbinado (coarse sugar)
Make the multigrain crust at least 3 hours in advance or up to a day. In a large bowl, whisk together the flours, sugar, and salt. Cut the butter into skinny shreds (as if you were cutting thin slices of cheese) and toss them into the flour mixture to coat. Using your hands, quickly incorporate the butter into the flour until the butter resembles pea-sized crumbles. Pour in half the ice-cold water. Use a large fork to bring the dough together. Continue adding water until dough holds together. Form into a shaggy rectangle.
On a lightly floured surface, press the dough out into a rectangle (about 8 x 4-inch). Cut dough in half and stack, placing the random bits in the middle. Repeat 3 more times, using flour as needed to keep the dough from sticking. Cut the dough almost in half, leaving one hunk slightly larger than the other (the bottom of the slab pie needs to be larger). Wrap each in plastic wrap and place in the freezer to chill for 20 minutes or in the fridge overnight.
Prepare the strawberry filling just before baking. Dice the strawberries in a similar size. Add to a large bowl and stir in the remaining filling ingredients. Set aside. Note: this recipe was developed with sweet, in season strawberries. If you’re strawberries aren’t noticeably sweet, you may want to add additional sugar.
Meanwhile, roll out the dough. On a well floured surface, roll out the larger hunk of crust until it’s large enough to extend about 1/2-inch over the lip of a quarter sheet pan, about 12 x 16-inches. If the crust sticks while rolling, add more flour. It should always be able to move during the rolling process. Fold into quarters and place in the quarter sheet pan. Unfold and evenly center within the pan. Place in the freezer while rolling out the top crust to a 9.5 x 12.5-inch rectangle. Cut out 12 evenly-spaced small stars, if desired. Nudge your star centering in slightly to account for the pie edge.
Once finished, remove the baking sheet lined with the bottom crust from the freezer. Pour in the strawberry filling, evening out the layer. Carefully top with the top crust. Fold the bottom crust edge over the top crust, evening out the edges if needed. Crimp to seal the two together. Place in the freezer for 20 minutes to firm up. This will help the pie to hold its shape in the oven. Meanwhile, preheat the oven to 400°F. Place a Baking Steel, Cast Iron Griddle, or an additional sheet pan in the oven to preheat. (Pizza Stone not recommended. See notes.) This will help the bottom crust to cook through. After 20 minutes, brush the pie crust with the egg wash. Sprinkle with turbinado. Place the pie on the preheated surface. Bake for 35-45 minutes or until golden. Note: If using a baking steel or pizza stone, the pie will cook on the faster side. If using a baking sheet, the pie may take the full time to cook.
Allow the pie to set and cool at least 1 hour before serving. Serve with a scoop of vanilla ice cream and a sprig of mint if desired. Leftovers can be stored at room temperature, lightly covered.
• Oat Flour can be purchased, but I always make mine at home, pulsing regular old fashioned oats in my Vitamix (substitute with a food processor) until a fine powder. I also use oats this way as an exfoliant at night while washing my face.
• Pizza Stones don’t handle heat differences well. Placing a pan from the freezer onto a hot stone may cause the stone to crack in the oven. For this reason, I switched to the Baking Steel a couple years ago and love it. If using a stone, you may want to forgo freezing the pie first. Note, you pie may not hold its shape as well while baking.