Preheat oven to 350 degrees. Grease and flour a 9x13 pan. Sift flour and baking powder together and set aside. Cream butter and the 1 cup sugar together until fluffy. Add eggs and the 1/2 tsp. vanilla extract; beat well. Add flour mixture to the butter mixture 2 Tbsp. at a time; mix until well blended. Pour batter into prepared pan. Bake at 350 degrees for 30 minutes. Pierce cake several times with a fork. Combine the whole milk, condensed milk, and evaporated milk together. Pour over the top of the cooled cake. Whip whipping cream, the remaining 1 cup of sugar, and the remaining 1 tsp. vanilla together until thick. Spread over the top of cake. Be sure and keep cake refrigerated. Enjoy!