Sweet Potato Casserole

Ingredients (16)

• 3 medium sweet potatoes
• 1 large egg
• 1/4 cup butter
• 1 pinch of salt
• 1/4 cup granulated sugar
• 1/3 cup brown sugar
• 1/2 teaspoon cinnamon
• 1/2 teaspoon vanilla
• 2 tablespoons milk or heavy cream
• Topping:
• 2 cups mini marshmallows
• 1/4 cup butter
• 1/2 cup all-purpose flour
• 1/2 cup brown sugar
• 1/2 teaspoon cinnamon
• 1/2 cup panko bread crumbs