Peel and core the honeycrisp apple, then slice it into thin 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 medium bowl. Coat each apple slice with this mixture and stack them in a ramekin until you reach the top. Press down on the layers a few times while stacking and pour out any excess liquid.
Once your ramekin is filled, pop it into a 400˚F oven for 10 minutes. After that, carefully remove excess liquid and crown your stack with a piece of puff pastry brushed with egg wash. Back into the oven for another 20 minutes.
For the best results, let it cool completely before serving. Gently release your creation from the ramekin with a butter knife, flip it upside down, and serve it with a generous scoop of ice cream. Enjoy!