For a different flavor profile, top these with lots of butter, some brown sugar, nutmeg, and pecans or black walnuts, and replace the sherry with bourbon or 1 teaspoon vanilla. Marshmallows may be substituted for the bread crumb and butter topping.
Bake until tender:
Reduce the oven temperature to 375°F. Halve the sweet potatoes lengthwise and scrape most of the pulp into a bowl, leaving ¼-inch shells. For a savory dish, season the pulp as for Twice-Baked Potatoes. For a sweet dish, mix in any of the suggestions in Mashed Sweet Potatoes, or add the following:
Beat with a fork until fluffy. Fill the shells and place on a baking sheet. If desired, cover the tops with:
Bake the sweet potatoes until browned, about 20 minutes.