Beat butter, shortening, and granulated sugar until light in color and fluffier in texture, about 3 minutes.

Beat in the eggs and vanilla for about 2 minutes.

Add the flour, baking powder, and salt to the mixing bowl and use a fork to lightly combine the dry ingredients. Then, stir in the dry ingredients until combined.

Cover and chill in the refrigerator for at least one hour.

Preheat oven to 400˚F.

Remove the dough from the refrigerator and roll it out to about 1/8-inch on a flour-covered surface.

Cut out mini heart shapes and use a spatula to transfer them to a parchment-covered baking sheet. Reroll the scraps until all of the dough has been used.

Bake at 400˚F for 4-6 minutes.

Cool completely before storing in an airtight container or before decorating.