Peel and core the apple, then slice it into 1/16” slices using a knife or mandoline (check out the one we used on our Amazon page).
Mix melted butter, sugar, and cinnamon in a bowl. Coat each apple slice with this mixture and stack them in a ramekin. Press down on the layers while stacking and pour out any excess liquid.
Bake in a 400˚F oven for 10 minutes. Afterward, pour out excess liquid, and top the stack with a piece of puff pastry brushed with egg wash. Bake for an additional 20 minutes.
For the best results, let it cool completely before serving. Use a butter knife to loosen the stack from the ramekin, then serve it upside down with a generous scoop of ice cream.
