Make the crust: In a large bowl, whisk together flour, sugar, and salt. Add cold cubed butter and use a pastry cutter or your fingertips to work it into the flour until the mixture resembles coarse crumbs with pea-sized butter pieces remaining.

Drizzle in ice water 1 tablespoon at a time, mixing gently with a fork until the dough just comes together. Divide dough in half, shape each into a disk, wrap in plastic wrap, and refrigerate for at least 1 hour or up to 3 days.

Prepare the filling: In a large bowl, toss sliced apples with lemon juice. In a separate bowl, combine granulated sugar, brown sugar, cornstarch, cinnamon, and nutmeg. Add to apples and toss until evenly coated. Let sit for 15 minutes.

Preheat oven to 425°F. On a lightly floured surface, roll out one dough disk into a 12-inch circle. Transfer to a 9-inch pie plate, letting excess hang over the edges. Pour apple filling into the crust, mounding slightly in the center, and dot with butter pieces.

Roll out the second dough disk into a 12-inch circle and place over the filling. Trim edges to 1-inch overhang, fold the top crust under the bottom crust edge, and crimp with your fingers or a fork to seal.

Cut 4-5 small vents in the top crust. Brush with heavy cream and sprinkle with cinnamon sugar. Place pie on a baking sheet and bake for 20 minutes.

Reduce oven temperature to 375°F and continue baking for 40-50 minutes until the crust is deep golden brown and filling is bubbling through the vents. If edges brown too quickly, cover with foil or a pie shield.

Cool on a wire rack for at least 3 hours before slicing to allow the filling to set completely. The pie will be very liquidy if cut too soon.