- 4 cups mashed sweet potatoes (about 3 jumbo sweet potatoes)
- 1 ⅓ cup granulated sugar
- ½ cup (1 stick) butter, softened
- 2 eggs, beaten
- ⅓ cup whole milk
- 2 teaspoons vanilla extract
- 3 to 4 cups miniature marshmallows
- Wash potatoes thoroughly and place in a large pot. Cover the potatoes with water and boil until fork tender. Remove peelings and place in mixing bowl.
- Using an electric mixer, beat sweet potatoes on high speed. Reduce speed and slowly add sugar. Beat well.
- Add butter; beat well. Add beaten eggs, milk, and vanilla extract. Beat until light and fluffy. (About 2 to 3 minutes)
- Pour into a greased or buttered 13 x 9 x 2-inch casserole dish. Bake in a preheated oven at 350 degrees F. for 30 minutes. Remove from oven and sprinkle with marshmallows. Return to oven and toast marshmallows until lightly browned and marshmallows are melting. Or for a crunchy taste brown longer.
Do ahead tip/freezer: Soufflé can be made 1day ahead before baking and kept in the refrigerator. Uncooked soufflé can be frozen for up to 2 months. Thaw in the refrigerator overnight before baking. Add 5 minutes to baking time.