Make the Cookie Dough

1. Preheat Oven: Preheat your oven to 350°F (175°C). Line two baking sheets with parchment paper.
2. Combine Dry Ingredients: In a medium-sized bowl, whisk together the flour, baking soda, and salt. Set aside.
3. Mix Wet Ingredients: In a separate large bowl, cream the softened butter, granulated sugar, and brown sugar until light and fluffy, about 3-5 minutes.
4. Add the Egg and Vanilla: Beat in the egg and vanilla extract until smooth and combined.
5. Add Dry Ingredients: Gradually add the dry ingredients to the wet ingredients, mixing until just combined. Be careful not to overmix.
6. Fold in Chocolate Chips: Gently fold in the mini chocolate chips until evenly distributed in the dough.
7. Chill the Dough: Cover the dough and refrigerate for at least 30 minutes to allow it to firm up slightly. This makes it easier to cut into shapes.

Shape the Cookies

1. Roll Out the Dough: On a lightly floured surface, roll out the dough to about 1/4 inch thickness.
2. Cut into Hearts: Using a heart-shaped cookie cutter, cut out cookies and place them on the prepared baking sheets, spacing them about 2 inches apart.
3. Bake the Cookies: Bake for 8-10 minutes, or until the edges are lightly golden but the centers are still soft.
4. Cool: Let the cookies cool on the baking sheets for 5 minutes before transferring to wire racks to cool completely.

Make the Frosting

1. Cream the Butter: In a medium bowl, beat the softened butter until smooth and creamy.
2. Add Powdered Sugar: Gradually add the powdered sugar, 1/4 cup at a time, until smooth and fluffy.
3. Add Vanilla and Milk: Stir in the vanilla extract and milk, adding more milk if necessary to achieve a spreadable consistency.
4. Color the Frosting: Divide the frosting into small bowls and color each with your desired food coloring.

Decorate the Cookies

1. Frost the Cookies: Once the cookies are completely cool, spread a layer of frosting on top of each cookie. Use a spatula or piping bag for a more decorative touch.
2. Add Sprinkles: Decorate with heart-shaped sprinkles, edible glitter, or any other fun decorations that match your Valentine’s theme.
3. Let the Frosting Set: Allow the frosting to set for about 15 minutes before serving.