Pour liquid of Mandarin oranges in small bowl. Add cake mix, butter and vanilla. Add eggs, one at a time. Chop up Mandarin oranges into small pieces. Beat all ingredients except Mandarin oranges for 3 minutes on mix setting. Add oranges and beat for one more minute. Pour into 3 greased and floured foil cake pans. Frosting: Combine vanilla pudding mix with cream cheese and pineapple juice. Add powdered sugar and crushed pineapple pieces. Fold in Dream Whip. Beat for 2 minutes. Frost cake.