Prep time: 20 minutes Cook time: 40-45 minutes Materials: 4 large eggs at room temperature separated 1/2 cup unsalted butter melted and cooled 2 cups whole milk warmed  1 cup powdered sugar  2 tbsp granulated sugar  1 tbsp. vanilla sugar (or vanilla extract) 2 tbsp. hot water 1 cup flour  Pinch of salt Additional powdered…