If using frozen puff pastry, make sure to thaw it out at room temperature 2 hours before.
In a pot, melt the butter.
In a bowl, pour the melted butter and sugar. Stir well.
Pour all the almond flour at once and stir well.
Add the eggs one by one. Mix some more.
Put a film wrap to contact on the almond filling and place it in the fridge for an hour.
Preheat oven at 400F.
Unroll the puff pastry and grab a plate (25 cm/10 inch) and the sharp knife. Place the plate upside down on the dough and with the knife cut around the plate to shape your cake.
With a little of water and a baking brush, wet the borders of the dough. It will allow the other sheet to stick better.
Take your almond filling out of the fridge and spread it in an even manner on the dough without going to close the edges.
Add your little charm if you have one.
Using the same plate, cut the other puff pastry dough in a round shape and place it on top of the other one where your spread the frangipane.
With a fork, squeeze the edge to allow the 2 sheets to seal. And, with your sharp knife, make some design on the top the cake, you need to make light scar marks, do not go deep in the dough.
Brush the pie with an egg yolk.
Bake for 30 minutes.