HEAT oven to 375ºF.
MIX first 5 ingredients until well blended; set aside. Beat next 5 ingredients in large bowl with mixer until well blended. Gradually beat in flour mixture. Pour into 8-inch round pan sprayed with cooking spray.
BAKE 35 to 40 min. or until golden brown. Cool in pan 10 min.; invert onto wire rack. Gently remove pan. Turn cake over; cool completely.
PLACE cake on plate. Mix cream cheese spread and Cool Whip with whisk until well blended. Stir in orange zest. Spread onto top and side of cake. Keep refrigerated.