Preheat oven to 350°F (175°C). Line a baking sheet with parchment paper.

In a small bowl, whisk flour, baking powder, and salt.

In a larger bowl, cream butter and sugar until light and fluffy. Add egg and vanilla, mixing well.

Slowly stir in dry ingredients until a soft dough forms.

Roll dough to 1/4-inch thickness on a floured surface. Cut out heart shapes and place on the baking sheet.

Bake for 8–10 minutes, until edges are just golden. Cool completely.

Sprinkle a thin, even layer of sugar on each cooled cookie.

Using a kitchen torch, melt the sugar until it bubbles and caramelizes. Let set for a crackly top.