Cinnamon-Bun Filled Pancakes

INGREDIENTS

• 1/2 cup granulated sugar
• 2 Tbs. all-purpose flour
• 1 1/2 Tbs. ground cinnamon
• 1/4 tsp. salt
• 4 Tbs. (1/2 stick) unsalted butter, cut into 1/2-inch cubes,
• at room temperature
• 3 oz. cream cheese, at room temperature
• 4 Tbs. (1/2 stick) unsalted butter, at room temperature
• 1 1/2 cups confectioners' sugar
• 3 to 4 Tbs. milk
• 2 cups all-purpose flour
• 1 tsp. baking powder
• 1/2 tsp. salt
• 1 Tbs. granulated sugar
• 4 eggs, separated
• 2 cups milk
• 4 Tbs. (1/2 stick) unsalted butter, melted, plus more for cooking