Heat oven to 425°F. Line cookie sheet with foil. Pierce sweet potatoes with fork; place on cookie sheet. Bake 1 hour 15 minutes or until tender. Cool at least 15 minutes. Reduce oven temperature to 350°F.
Meanwhile, sprinkle pecans in ungreased heavy skillet. Cook over medium heat 5 to 7 minutes, stirring frequently until nuts begin to brown, then stirring constantly until nuts are light brown. Remove from skillet; set aside.
In same skillet, melt butter over medium-high heat. Cook apple and raisins in butter 2 to 3 minutes, stirring occasionally, until apple is tender. Stir in brown sugar, cinnamon and nutmeg. Remove from heat.
Cut each sweet potato lengthwise in half; scoop pulp into large bowl, leaving thin shells. Add apple mixture to pulp in bowl; stir until blended. Spoon mixture into shells. Place on ungreased cookie sheet.
Bake 15 to 20 minutes or until thoroughly heated. Top with toasted pecans.