The flavors of this pie are inspired by a bowl of hearty oatmeal—a breakfast that feels simultaneously nourishing and like a special treat. I take mine lightly sweetened with a little maple syrup, enriched with butter, and topped with walnuts and a pinch of cinnamon. For this pie filling, oats are cooked in browned butter and cream until the mixture is thick, then it’s whisked into the brown sugar base. While it quite literally recalls oatmeal, the pie is also a faithful, delicious, and corn syrup-free interpretation of the classic pecan pie recipe from Karo syrup, so consider it for your Thanksgiving dessert table. This is the only pie in the book that requires weighting the crust and baking it prior to adding the filling and baking it again, a process called parbaking. It’s an extra few steps, but if you follow the method below, you will have a crisp and not soggy crust, which for me makes the parbaking essential.
- PREHEAT THE OVEN: Arrange an oven rack in the center position and preheat the oven to 400°F.
- TOAST THE NUTS AND SOME OF THE OATS: Scatter the walnuts and 3 tablespoons of the oats on a sheet pan and toast until the walnuts are golden brown and fragrant, 7 to 10 minutes, tossing halfway through. Set the pan aside and let the nuts and oats cool. Leave the oven on for parbaking the crust.
- PORTION THE DOUGH: Remove the dough from the refrigerator and unwrap. You will need two-thirds of the total dough for this slab pie, so use a knife or bench scraper to slice off about one-third of the dough. Wrap the smaller piece and return to the refrigerator for another use.
- ROLL OUT THE DOUGH: Let the dough sit at room temperature for a minute or two to soften slightly, then place it on a lightly floured surface. Use a rolling pin to beat the dough all across the surface to make it more pliable. Dust more underneath and on top of the dough, then roll it out, dusting with more flour as needed, into a rectangle measuring about 15 × 12 inches (for step-by-step visuals, see Rolling Out Chilled Pastry Dough, page 332).
- LINE THE QUARTER-SHEET PAN: Roll the pastry onto the rolling pin, then unroll it onto a 13 × 9-inch sheet pan, centering it so you have equal overhang along all four sides. Firmly press the pastry into the bottom and against the sides of the pan, ensuring contact everywhere and taking care not to stretch it. Use scissors to trim the edges of the pastry, leaving a ½-inch overhang all the way around (discard the scraps). Tuck the overhang underneath itself so you have a thick border of pastry resting on the rim of the pan along all four sides. Using your thumb on one hand and your thumb and forefinger on the other, crimp the border, flouring your fingers if needed to prevent sticking.
- PARBAKE THE CRUST: Freeze the pan until the dough is very firm, 10 to 15 minutes, then prick the dough in several places across the bottom of the pan with a fork to prevent it from puffing up as it bakes. Line the pan with a double layer of foil, pressing the pieces into the bottom and up the sides and leaving several inches of overhang on all sides. Fold the overhang down and over the crimped edge of the dough to cover. Fill the pan with dried beans or rice and spread them in an even layer, then place the lined pan on a larger sheet pan. Bake until the edge of the crust is set and starting to turn golden when you peek underneath the foil, 25 to 30 minutes, then remove it from the oven. Leave the oven on and reduce the temperature to 325°F.
- CONTINUE BAKING THE CRUST: Very carefully use the overhanging foil to lift the pie weights out of the crust and set them aside. Return the sheet pan to the oven and bake until the crust is golden brown across the bottom, 25 to 30 minutes longer, then remove it from the oven. While the crust is baking, prepare the filling.
- COOK THE BUTTER AND REMAINING OATS: In a small saucepan, combine the butter and remaining ½ cup (1.4 oz / 40g) oats and cook over medium heat, stirring occasionally with a heatproof flexible spatula, until the butter is melted. Increase the heat to medium-high and bring the mixture to a boil, stirring constantly. Continue to cook, stirring all the while, until the oats are deep golden brown and the butter is foaming and you see tiny brown specks swimming in the foam, 10 to 15 minutes. Remove the saucepan from the heat.
- ADD THE CREAM: Slowly add the cream to the saucepan, stirring constantly (be careful, it will sputter aggressively at first). Once all the cream is added, bring the mixture to a simmer over medium-low heat and cook, stirring constantly, until it’s thickened to the consistency of a loose porridge, about 2 minutes. Remove the saucepan from the heat and set aside.
- MAKE THE FILLING: In a large bowl, whisk together the whole eggs, egg yolks, brown sugar, maple syrup, vanilla, salt, and cinnamon until the eggs are broken up, then whisk vigorously until the mixture is completely smooth and streak-free. Whisking constantly, slowly pour in the hot cream mixture. Set the filling aside until the crust is finished parbaking.
- ASSEMBLE THE PIE AND BAKE: Scatter the toasted walnuts and oats across the bottom of the hot parbaked crust in an even layer. Whisk the filling again and pour it into the crust, evenly distributing the cooked oats that have settled to the bottom of the bowl (the heat in the crust will set the bottom layer of filling quickly, preventing sogginess, and will help the pie cook faster). Transfer the sheet pan to the oven and bake until the filling is slightly puffed and the center is firm to the touch, 22 to 28 minutes. Transfer the pie to a wire rack to cool completely.
- COMBINE THE DRY INGREDIENTS: In a large bowl, whisk together the flour, sugar, and salt.
- ADD THE BUTTER AND ICE WATER: Prepare about 1 cup (8 oz / 227g) of ice water and set it aside. Add the butter to the bowl with the dry ingredients and toss, separating the pieces and coating them in the flour mixture. Use your fingertips to quickly break and smash the pieces of butter into smaller bits (it’s okay if some of the butter is left in large pieces; you’ll break it up more in the next step). Make a well in the center of the bowl and add 2⁄3 cup (5.6 oz / 158g) of the ice water. Toss with a fork to distribute the water until you have a clumpy mixture with lots of dry spots [A].
- WORK THE MIXTURE DIRECTLY ON THE SURFACE: Tip the contents of the bowl out onto a clean work surface [B]. Use the straight edge of a bench or bowl scraper to chop up the mixture directly on the surface, breaking up the clumps and pieces of butter and periodically using the scraper to toss and push the mixture back into a pile. Continue to chop and toss the mixture until it’s broken down into small, uniform pieces with very few floury spots and the butter pieces are no larger than a pea [C, D]. This process helps you bring the dough together without working it excessively, increasing tenderness.
- BRING THE DOUGH TOGETHER: Push the mixture into a pile and squeeze it with your hands all over so it holds together in large pieces [D]. Depending on the butter and flour you're using, the entire mixture might hold together without any dry spots—if that’s the case, skip to the next step. If you still have some floury areas, move any large pieces to one side, leaving the dry bits in the pile. Drizzle ½ tablespoon of ice water over the floury area, then use the bench scraper in the same chopping motion to evenly distribute the water [E]. Squeeze to bring it together, moving the pieces to the side, then repeat with more ice water as needed until no dry flour remains on the surface.