Preheat your oven to 350°F (180°C) and line your baking sheet with parchment paper.

In a medium bowl, whisk together the flour, baking powder, baking soda, salt, and cocoa powder.

In a large bowl, beat the butter and sugars until light and fluffy. Add egg and vanilla, mixing well.

Gradually add dry ingredients and buttermilk, alternating them, until well combined. Add food coloring to desired shade.

Pipe the batter onto the prepared baking sheet in heart shapes, leaving space between them. Bake for about 10 minutes.

Allow cookies to cool on the baking sheet for 5 minutes, then transfer to a wire rack to cool completely.

Beat cream cheese and butter until smooth, add powdered sugar and vanilla, mix until fluffy.

Pipe cream cheese filling onto half of the cooled cookies and sandwich them with the remaining cookies.