In a large mixing bowl, add the flour, sugar, and salt.

Cut the butter into small chunks and add to the bowl.

Using a pastry blender or fork, cut the butter into the flour mixture until you have coarse crumbs.

Add the cold water and begin to mix together with a fork. Add additional cold water 1 Tbsp. at a time if needed until the dough comes together well.

Press the dough into a ball or disc, wrap in plastic wrap, and refrigerate for 30 minutes

While the dough is chilling, add apples, sugar, cinnamon, and lemon juice to a large mixing bowl. Set aside until dough is ready.

When the dough is ready, lay out one sheet of parchment paper and lightly flour. Place the dough onto the floured surface. Cover the dough with an additional sheet of parchment paper and roll out into a large 12-14 inch circle – or just roll out with a floured rolling pin.

Place sliced apples into the center of the dough, then carefully fold up the edges, letting them naturally fold in.

Carefully transfer the dough, bottom parchment paper and all, to a baking sheet. Trim the parchment paper so that it’s not hanging over any edges of the baking sheet.

In a small bowl, whisk the one egg and brush over the crust edge – sprinkle additional sugar across the entire galette and place into the oven to bake.

Bake for 30 minutes, then remove from oven and let slightly cool before serving.