Mix cake mix as directed,add vanilla,add thawed frozen strawberrys.
In two 9'' round cake pans add a couple tbs. vegetable oil to each. Spread all around bottom and sides with papertowels untill even, blot out access. Sprinkle some flour into each pan. Shake flour all around bottom and sides untill coated, on the back of pan pat out access flour over sink.
Spoon cake mixture evenly into both pans. Bake on 350 for about 25 mins. or untill toothpick comes out cleanly when inserted through the middle.Cool completely.
Clean,then on a cutting board cut tops off strawberrys. Cut strawberrys into pieces,then dice into small pieces ,add to cool whip with two tbs instant vanilla pudding.Mix all togeather.
When cooled carefully remove one of the cakes,and flip upside down on cake platter. Frost top with coolwhip mixture, add other cake right side up and frost top and sides of cake. Decorate top of cake with remaining strawberry's. Refrigerate one hr. Store in fridge!