Combine the flour, baking powder, salt, 1 3/4 cup sugar, and milk powder in a large mixing bowl; stir well.
Add melted butter (1 cup + 2 tablespoons), 2 eggs, and 1 1/2 teaspoons vanilla; beat at medium speed of an electric mixer until the mixture is well blended. Pour the batter into a greased 15 x 10 x 1 inch jellyroll pan.
Beat the cream cheese at medium speed of an electric mixer until smooth. Add 2 eggs and 1 teaspoon vanilla; beat well. Add the powdered sugar, and beat until the mixture is smooth.
Spread the cream cheese mixture evenly over the batter. Bake at 350 degrees for 25 to 30 minutes or until the top is golden brown. Let the cake cool in the pan on a wire rack; cut into squares.