Preheat the oven to 375°F.

Roll out one refrigerated pie crust and fit it into an 8-inch round baking dish. Keep the second crust chilled for the lattice.

Peel, core, and slice all ten Granny Smith apples. Set aside.

In a large saucepan, melt the butter over medium heat. Add the sliced apples, granulated sugar, brown sugar, cinnamon, nutmeg, cornstarch, and salt. Stir to coat. Cook for 5 to 7 minutes, stirring occasionally, until the mixture thickens and turns syrupy. Remove from the heat.

Stir in the heavy whipping cream and ¼ cup of the caramel sauce. Mix until smooth and combined. Reserve the remaining ¼ cup of caramel for serving.

Pour the thickened apple filling into the prepared pie crust. Spread evenly.

Roll out the second pie crust. Cut it into strips about 1 inch wide. Lay half the strips across the pie in one direction. Fold back every other strip and lay a strip across in the opposite direction. Repeat until the top is covered. Trim the overhang and press the edges to seal.

Whisk the egg in a small bowl. Brush generously over the lattice crust, covering every strip and the edges.

Sprinkle a pinch of coarse salt over the top of the lattice.

Bake for 30 to 35 minutes, until the crust is golden brown and the filling is bubbling through the lattice gaps.

Remove from the oven and let the pie cool for at least one full hour before slicing. The filling needs time to set.

Serve with whipped cream and the reserved caramel sauce drizzled on top.