Brown Butter Apple Pie

Preparation

Nutty, caramelized brown butter is featured in two ways in this crowd-pleasing skillet pie. It starts in the crust, in which chilled browned butter stands in for plain butter. Then, the filling is made by combining crunchy fresh apples with apples cooked in browned butter caramel, with just the right amount of cinnamon and vanilla bean to tie it all together. 

1. Make the dough. In a HexClad 10"/25 cm Hybrid Fry Pan, cook butter over medium heat, swirling occasionally, until deep golden brown and nutty smelling, 4 to 5 minutes. Pour into a loaf pan and let cool. Once cool to the touch, freeze until firm, at least 20 minutes. 
2. Invert chilled browned butter onto a cutting board (you may need to use a rubber spatula to pry it out) and cut into small cubes. Transfer to a food processor with flour, sugar, and salt and pulse until pea-sized pieces begin to form, about 30 seconds. While pulsing, stream in ice water and vinegar; the dough should look pebbly but stick together when pinched. If it doesn’t, pulse in more ice water, 1 tablespoon at a time, until dough comes together when pinched.
3. Divide dough in half and wrap each in plastic, patting to form 1 in/2½ cm-thick-disks. Press dough and smooth rough edges until there are no visible cracks. Refrigerate for at least 2 hours or preferably overnight. 
4. Make the pie. Position rack in middle of oven and preheat to 425°F/220°C. Line a rimmed baking sheet with foil or parchment; set aside. In a large bowl, toss apples, brown sugar, lemon juice, cornstarch, vanilla, cinnamon, and salt. Let sit for 20 minutes.
5. In a clean HexClad 10"/25 cm Hybrid Fry Pan, cook butter over medium heat, swirling occasionally, until deep golden brown and nutty smelling, 3 to 4 minutes. Add half the apples and all the juices that have accumulated in the bowl, and cook, stirring occasionally, until apples are softened and sauce has thickened, 6 to 7 minutes. Pour mixture back into remaining sliced apples and stir to combine. Let cool slightly. 
6. Meanwhile, on a lightly floured surface, roll out one disk of dough to a 14 inches/4 cm round and transfer to a clean HexClad 10"/25 cm Hybrid Fry Pan. Press dough into pan and trim to leave 1 inch/2½ cm of overhang. Refrigerate while preparing lattice top. 
7. Roll out second disk of dough to same dimensions. Cut into 8 strips, each 1 ½ inches/2½ cm wide. 
8. Transfer filling to pie plate and smooth into an even layer. Arrange four dough strips parallel across center of pie filling, with about 1 inch/2 ½ cm between. Fold one strip halfway back on itself, then arrange a new strip perpendicular across center of pie, crossing over one of first two strips, then unfold other strip over it to create a woven effect. Repeat, folding back opposite parallel strip and adding a second perpendicular strip. Fill in sides with remaining four strips, repeating weaving pattern, until the pie is fully covered in a crisscross pattern. Bring together overhanging strips and dough on bottom, then crimp into a decorative pattern.
9. In a small bowl, whisk egg and 1 tablespoon water. Brush egg wash over crust and sprinkle all over with sanding sugar. Place on prepared baking sheet. Bake 5 minutes, then reduce oven temperature to 375°F/190°C and bake, rotating once halfway through, until filling is thick and bubbling and crust is golden brown, 50 to 60 minutes; tent pie with foil if top crust is browning too quickly. Cool on a wire rack for at least 1 hour before serving to allow filling to set. Serve with vanilla ice cream, if desired.
   

MAKE AHEAD TIPS

The brown butter for the crust can be prepared, chilled to room temperature and frozen in an airtight container for up to 2 weeks. The brown butter can be used directly from the freezer to make the crust. The pie dough can be wrapped tightly in plastic wrap refrigerated for up to 2 days. The pie filling can be refrigerated in an airtight container overnight. The baked pie can be covered and kept at room temperature for up to 2 days.