FOR THE CREAM CHEESE FILLING: – 4 ounces (113g) cream cheese, at room temperature – 2 tablespoons granulated sugar – 1/2 teaspoon vanilla extract – 1 egg yolk FOR THE MUFFINS: – 1 & 1/2 cups (180g) all-purpose flour – 1/2 cup (100g) granulated sugar – 1/4 cup (50g) packed light brown sugar – 1 teaspoon baking powder – 1/2 teaspoon baking soda – 1/2 teaspoon salt – 1/2 cup (113g) unsalted butter, melted and cooled to lukewarm – 1 large egg – 1 teaspoon vanilla extract – 3 medium ripe bananas, mashed (about 1 cup) – 1/3 cup (79ml) milk – about 1 cup chopped pecans, optional – sanding sugar, optional