Place 6 tablespoons butter in a 10-inch ovenproof skillet (preferably cast iron) in a 400 degree F oven until butter melts. In a medium bowl, beat eggs until combined. Add flour, milk, 1/4 teaspoon nutmeg, and the salt; beat until smooth. Immediately pour batter into the hot skillet. Bake for 20 to 25 minutes or until puffed and well browned.
In a medium saucepan, melt the 2 tablespoons butter. Add apples and raisins; cook over medium heat until apples are almost tender; stir frequently. Add the brown sugar and 1/4 teaspoon nutmeg. Cook and stir until apples are well coated and glazed. Remove from heat. If you like, stir in the nuts. Set aside.
Transfer pancake to a large serving platter. Spoon filling into the center of the pancake. If you like, sprinkle with sifted powdered sugar or serve with whipped cream. Serve immediately. Makes 6 servings.