Pierce potatoes in several times with fork. Arrange potatoes on a baking sheet. Bake until potatoes are tender, about 60 minutes.
Reduce oven to 375°F (190°C). Let sweet potatoes cool slightly. Slice in half lengthwise; scoop out pulp into medium bowl. Mash pulp with Becel® Buttery Taste margarine* until desired consistency. Stir in maple syrup and nutmeg.
Spoon into lightly greased casserole dish**. Bake covered until heated through, about 20 minutes.