1 Preheat oven to 350°F. For the Crumb Topping, mix walnuts, flour, brown sugar and spices in medium bowl. Cut in butter with pastry blender or 2 knives until mixture resembles coarse crumbs.
2 For the Cake, mix flour, cream of tartar, baking soda and salt in small bowl; set aside. Beat butter, granulated sugar and vanilla in large bowl with electric mixer on medium speed 5 minutes or until light and fluffy. Beat in eggs and sour cream on low speed just until blended. Gradually beat in flour mixture until blended. Spread evenly in greased 13x9-inch baking pan. Drain peach pieces on paper towels. Arrange peaches over top of batter, pressing in slightly. Sprinkle with Crumb Topping.
3 Bake 45 to 50 minutes or until cake pulls away from sides of pan and topping is browned. Cool in pan on wire rack.