From www.epicurious.com reprinted from Gourmet November, 2001

6 lb sweet potatoes                                           1 stick (1/2 cup) unsalted butter, melted
1/2 cup heavy cream, warmed                          2 tablespoons pure maple syrup
1 teaspoon salt                                                 1/2 teaspoon black pepper

Preheat oven to 400°F. 

Prick each potato twice with a fork and bake in a foil-lined shallow baking pan in lower third of oven until very tender, about 1 hour. Remove and cool slightly.  Halve potatoes lengthwise and scoop out warm flesh into a large bowl. Mash potatoes with a potato masher or, for a smoother purée, force through a potato ricer. Stir in butter, cream, syrup, salt, and pepper.

Makes 10 servings.