To prepare a twice baked sweet potatoes with browned butter and toasted marshmallows recipe, you'll need: Sweet potatoes: Peel and cut sweet potato into halves. Brown butter: Melt 2 tablespoons butter over medium-low heat. Stir in 2 teaspoons brown sugar. Cook, stirring, until the sugar dissolves. Remove from heat and stir in 1/2 cup granulated white sugar, 1 teaspoon cinnamon, and 1/4 teaspoon nutmeg. Spread on ungreased baking sheet. Bake in the preheated oven for 20 to 25 minutes or until tender. Serve warm.