Prep Time 20 minutes mins
Cook Time 18 minutes mins
Resting Time 30 minutes mins
Total Time 1 hour hr 8 minutes mins
For best results, avoid overmixing the batter after adding the dry ingredients to keep the cupcakes soft and tender, and always start with room-temperature butter, eggs, milk, and sour cream so the batter emulsifies smoothly and bakes evenly. If your frosting seems too stiff, add cream a teaspoon at a time until it pipes easily, and if it becomes too soft, chill it for 10 to 15 minutes before piping. You can bake the cupcakes a day ahead and store them unfrosted in an airtight container at room temperature, then frost shortly before serving for the freshest texture. For neater heart-themed decoration, hold the piping bag straight up and keep steady pressure as you swirl, and use a toothpick dipped in food coloring to draw tiny hearts or accents directly on the frosting for extra detail.