Cut the puff pastry with a heart-shaped cookie cutter. Cut enough pieces to have a top and bottom for each heart.
Layer graham cracker in a heart shape on top of the puff pastry, keeping it away from the edges.
Then, pipe a layer of cheesecake in a zigzag pattern on top of the graham cracker crumbs.
Crumble the red velvet cupcakes and sprinkle some on top of the cheesecake, covering the cheesecake as much as possible.
Pipe another layer of cheesecake on top of the cake, making sure to stay away from edges.
Put a puff pastry heart on top of the layers; line it up to meet the edges of the bottom heart.
Using the same cookie cutter push down to cut the edges off the heart and seal the pastry together.
Brush with egg yolks and bake at 365°F until golden brown, turning over once.