Cinnamon Heart Cookies - "palmiers"

Preheat oven to 450. Line 2 baking sheets with parchment paper. Combine sugar and cinnamon in bowl. Sprinkle work surface with 1/4 cup mixture.

Open 1 puff pastry sheet, with 3 fold lines parallel to edge of work surface. Roll with rolling pin 3 times to close any cracks. Spread 2 tablespoons sugar mixture on puff pastry. Roll lightly to press in sugar mixture. Flip, and repeat to coat second side.

Fold short ends to first fold line. Fold again so 2 folds meet at middle of dough. Fold 1 half over other to make log. Cut into 15 slices. Dip cut sides in remaining sugar on work surface, and place on prepared baking sheet, cut-side up. Repeat with remaining puff pastry and sugar mixture.

Bake 6 minutes, or until sugar begins to caramelize on bottoms. Flip with spatula, and bake 3-5 minutes more, or until caramelized on both sides. Cool on wire rack.