1/2 cup butter, softened
1/2 cup vegetable oil
1/2 cup sugar
4 eggs
1 package (18-1/2 ounces) butter recipe golden cake mix
1 cup (8 ounces) sour cream
FILLING:
1/2 cup chopped walnuts
1/4 cup packed brown sugar
4 teaspoons ground cinnamon
TOPPING:
1/4 cup all-purpose flour
1/4 cup sugar
2 teaspoons ground cinnamon
1/4 cup cold butter
Recipe
In a large mixing bowl, cream butter, oil and sugar. Add eggs, one at a time, beating well after each addition. Gradually add cake mix; mix well. Beat in sour cream just until combined.
Pour half of the batter into a greased 13-in. x 9-in. x 2-in. baking pan. Combine the filling ingredients; sprinkle over batter. Top with remaining batter. Cut through with a knife to swirl.
For topping, in a small bowl, combine the flour, sugar and cinnamon. Cut in butter until mixture resembles coarse crumbs. Sprinkle over batter.
Bake at 350° for 40-45 minutes or until a toothpick inserted near the center comes out clean. Cool on a wire rack. Yield: 12-15 servings.