Coat bottoms of 2 (9-inch) round cake pans with cooking spray (do not coat sides of pan); line bottoms with wax paper. Coat wax paper with cooking spray; dust with 1 tablespoon flour.
Beat sugar, butter, and vanilla at medium speed of a mixer until well-blended (about 5 minutes). Add eggs, 1 at a time; beat well after each addition. Lightly spoon 2 1/4 cups flour into dry measuring cups; level with a knife. Combine with baking powder and salt; stir well with a whisk. Add flour mixture to sugar mixture alternately with milk, beginning and ending with flour mixture.
Pour batter into prepared pans. Sharply tap pans once on counter to remove air bubbles. Bake at 350° for 30 minutes or until a wooden pick inserted in center comes out clean. Cool in pans 10 minutes on a wire rack; remove from pans. Remove wax paper. Cool completely on wire rack.
Place 1 cake layer on a plate; spread with 1/2 cup Caramel-Pecan Frosting, and top with remaining layer. Spread remaining frosting over top and sides of cake. Store cake loosely covered in refrigerator.