01 - In a medium bowl, whisk together flour, baking powder, and salt. Set aside.
02 - In a large bowl, cream together the butter and sugar until light and fluffy, about 2 to 3 minutes.
03 - Add the egg and vanilla extract to the butter mixture, mixing until combined.
04 - Gradually add the dry ingredients to the wet ingredients, mixing on low speed until just combined.
05 - Divide dough in half, flatten into disks, wrap in plastic wrap, and chill for at least 1 hour.
06 - Preheat oven to 350°F. Line baking sheets with parchment paper.
07 - On a lightly floured surface, roll dough to 1/4-inch thickness. Cut into heart shapes using a cookie cutter.
08 - Place cookies 1 inch apart on prepared baking sheets.
09 - Bake for 8 to 10 minutes, or until edges are just barely golden. Cool on the sheet for 5 minutes, then transfer to a wire rack to cool completely.
10 - Beat together powdered sugar, milk, butter, and vanilla until smooth. Add food coloring and mix until desired pink shade is reached.
11 - Spread or pipe frosting onto cooled cookies. Allow frosting to set before serving.