Apple Cake with Buttery Caramel Sauce

Preheat oven. Grease a 13x9x2-inch baking pan; set pan aside. In a medium bowl stir together flour, baking powder, salt, nutmeg, cinnamon, and baking soda; set aside. In a very large mixing bowl beat butter with an electric mixer on medium to high speed for 30 seconds. Gradually add sugar, about 1/4 cup at a time, beating on medium speed until well combined. Scrape side of bowl; beat for 2 minutes more. Add eggs one at a time, beating well after each addition. Add flour mixture to butter mixture, beating on low speed just until combined. Fold in apples and walnuts. Spread batter in prepared pan. Bake for 45 to 50 minutes. Cool in pan on wire rack for 45 minutes. Serve with Sauce. BUTTERY CARAMEL SAUCE In a small saucepan melt butter over medium heat. Stir in granulated sugar, brown sugar, and whipping cream. Bring to boiling, stirring constantly. Remove from heat; stir in vanilla. Serve warm.