Chiffon Cheesecake| Pinoy style Cheesecake| Soft and Fluffy

Ingredients:
4 egg yolks
1/4 cup sugar
1/4 cup oil
1/3 cup milk
1/2tsp vanilla
1 cup ap flour
1/2tsp salt
4 egg whites
1/2 tsp cream of tartar
1/3 cup sugar
buttercream frosting:
1/2 cup softened butter
1/2 cup chilled condense
1/4 cup powder sugar