PREHEAT oven to 350°F Spray 9-inch square baking pan with cooking spray; set aside. Mix cereal, cinnamon and 2 tablespoons melted butter until well blended; set aside for later use. Combine flour, baking soda, baking powder and salt in another bowl.
BEAT 1/2 cup butter in large bowl with electric mixer on medium speed until creamy. Gradually add sugar, beating until light and fluffy. Add eggs, 1 at a time, beating well after each addition. Blend in vanilla. Add flour mixture alternately with the sour cream, beating well after each addition. Pour half of the batter into prepared pan; sprinkle with half of the cereal mixture. Repeat layers.
BAKE 40 minutes or until toothpick inserted in center comes out clean. Cut into 16 pieces. Serve warm.