Overnight Blueberry French Toast Casserole

Bahan-bahan (6 porsi)

• 8 ounces French bread (I used half of a 1-pound loaf)
• 4 eggs
• 1/2 cup milk
• 1/4 teaspoon baking powder
• 1 teaspoon vanilla
• 4 & 1/2 cups blueberries (*)
• 1/2 cup sugar
• 4 teaspoons cornstarch
• 2 teaspoons cinnamon
• 2 tablespoons butter (melted (I recommend Land O'Lakes ))
• powdered sugar (to garnish)