Banana Split Cupcakes

self-rising flour1 1/2 cups all-purpose flour1 cup (2 sticks) unsalted butter, softened2 cups sugar4 large eggs, at room temperature1 cup milk1 cup banana puree1 teaspoon vanilla extract

bananas1 cup milk1 cup heavy cream¼ cup corn starch½ cup sugar, plus 2 tablespoon sugar1 tablespoon vanilla¼ kosher salt

large egg whites11/2 cup sugar4 sticks unsalted butter, diced and softened1/4 teaspoon salt1 1/2 teaspoons vanillas extract