Preheat and Prepare Pans
Preheat your oven to 350°F (175°C). Grease and flour one 8-inch square pan and one 8-inch round pan.

Mix Dry Ingredients
In a medium bowl, whisk together the flour, baking powder, baking soda, and salt. Set aside.

Cream Butter and Sugar
In a large mixing bowl, beat the butter and sugar until light and fluffy. Add eggs one at a time, then mix in the vanilla extract.

Combine Wet and Dry Ingredients
Alternate adding the dry ingredients and the buttermilk/milk to the butter mixture, beginning and ending with the dry ingredients. Stir in the red food coloring, if using.

Bake the Cake
Divide the batter between the square and round pans. Bake for 25–30 minutes, or until a toothpick inserted in the center comes out clean. Let cakes cool completely.

Assemble the Heart Shape
Cut the round cake in half. Position the square cake diagonally (like a diamond), and place each half-circle on the top sides to form a heart.

Make the Frosting
Beat butter until smooth. Gradually add powdered sugar, then mix in cream and vanilla. Add food coloring, if desired.

Frost and Decorate
Spread frosting evenly over the cake. Decorate with sprinkles, fresh berries, or piped designs.