1/4 cup butter (no substitutes), softened
1 cup sugar
1 egg
1 teaspoon vanilla extract
1 cup all-purpose flour
1 teaspoon baking soda
1/2 teaspoon ground cinnamon
1/4 teaspoon salt
1/4 teaspoon ground nutmeg
2 medium tart apples, peeled and grated
1/2 cup chopped walnuts
BUTTER SAUCE:
1/2 cup butter
1/2 cup sugar
1/2 cup packed brown sugar
1/2 cup half-and-half cream

In a mixing bowl, cream butter and sugar. Beat in egg and vanilla. Combine the flour, baking soda, cinnamon, salt and nutmeg; gradually add to the creamed mixture. Stir in apples and walnuts. Pour into a greased 8-in. square baking dish. Bake at 350 degrees F for 40-45 minutes or until a toothpick inserted near the center comes out clean.
Meanwhile, in a saucepan, melt butter. Stir in sugars and cream. Bring to a boil over medium heat, stirring constantly. reduce heat. Simmer, uncovered, for 15 minutes, stirring occasionally. Serve over warm cake.

Source: allrecipes.com