Ladybug Cupcakes

Ingredients

• pinch of salt
• 5 large egg whites
• 2 1/4 cups sugar
• 3/4 teaspoon baking soda
• 2 1/4 teaspoons baking powder
• 1 1/2 cups all-purpose flour
• 2 teaspoons pure vanilla extract
• 1 cup plus 2 tablespoons sugar
• 1 1/2 teaspoons coarse salt
• 3 cups cake flour (not self-rising)
• 1 cup plus 2 tablespoons unsalted butter (at room temperature)
• 5 large whole eggs plus 3 egg yolks (at room temperature)
• 2 cups buttermilk (at room temperature)
• 1 pound 4 sticks unsalted butter, cut into tablespoons, at room temperature
• Red (green and black gel-paste food coloring)
• 7 ounces marzipan
• Cornstarch (for work surface)