
In a large bowl, combine flour, sugar, and baking powder. Mix well.
Add eggs on at a time and using an electric mixer, beat after each addition.
Add milk and beat until smooth.
Add water and continue to beat until batter is thin and smooth.
Add butter and vanilla extract. Stir until well blended.
Add the shredded cheese and stir until combined.
Fill molds with batter up to 3/4 full. Arrange molds in a single layer on steamer rack and place over steamer.
Steam for about 8 to 10 minutes or until a toothpick inserted comes out clean.
Turn off the heat and top each puto with a slice of cheese. Cover for about 1 minute to allow the residual heat to melt the cheese.
Allow to slightly cool before removing from molds.