Preheat oven to 350°F and line two baking sheets with parchment. Whisk flour, baking powder, and salt in a bowl.

Beat butter and sugar until fluffy, about 2 to 3 minutes. Add egg, rose water, and vanilla, then beat until smooth.

Gradually mix in dry ingredients just until no white streaks remain.

Scoop tablespoon-sized mounds of dough onto the sheets, spacing them 2 inches apart.

Bake for 10 to 12 minutes until edges are just set. Cool on the sheet for 5 minutes, then transfer to a rack. Sprinkle with rose petals while warm.