1. Make the Cake:

1. Preheat your oven to 350°F (175°C). Line a 9×13-inch baking pan with parchment paper and lightly grease it.
2. In a medium bowl, whisk together the flour, baking powder, baking soda, and salt.
3. In a large bowl, cream together butter and sugar until light and fluffy. Add eggs one at a time, beating well after each addition. Mix in vanilla extract.
4. Gradually alternate adding the dry ingredients and buttermilk to the wet mixture, beginning and ending with the dry ingredients.
5. Add a few drops of gel food coloring and mix until the batter is evenly tinted.
6. Pour the batter into the prepared pan and smooth the top. Bake for 18-22 minutes, or until a toothpick inserted in the center comes out clean. Let the cake cool completely.

2. Prepare the Frosting:

1. In a large bowl, beat the butter until creamy. Gradually add powdered sugar, mixing until smooth.
2. Add heavy cream and vanilla extract, and beat until fluffy. For color, mix in food coloring until the desired shade is achieved.

3. Cut and Assemble the Mini Cakes:

1. Use a heart-shaped cookie cutter to cut out mini hearts from the cooled cake. (You should get about 12-15 hearts, depending on cutter size.)
2. Spread or pipe frosting on one heart-shaped piece and top it with another to create a sandwich. Repeat with the remaining pieces.

4. Decorate the Cakes:

1. Frost the tops and sides of each mini heart cake, smoothing with an offset spatula.
2. Decorate with sprinkles, edible glitter, candy hearts, or drizzle with melted chocolate.

5. Serve and Enjoy:

• Serve immediately or store in an airtight container in the refrigerator for up to 3 days.