1. Preheat oven to 400°.
2. Pierce potatoes several times with a fork; place on a foil-lined baking sheet. Bake at 400° for 1 hour or until tender. Cool slightly; peel and mash in a large bowl.
3. Reduce oven temperature to 350°.
4. Stir half-and-half and the next 8 ingredients (through egg) into sweet potatoes. Spoon mixture into a 2-quart baking dish coated with cooking spray. Bake at 350° for 15 minutes. Sprinkle the top with mini-marshmallows and chopped pecans; bake 12 minutes or until the mini-marshmallows are slightly melted. Serve immediately.