Whisk cake flour, baking powder, and salt in a medium bowl until evenly mixed.
In a large bowl, whisk sugar, eggs, melted butter, milk, water, and vanilla extract until smooth.
Add the dry ingredients to the wet ingredients and whisk until you no longer see dry flour. Do not overmix.
Stir in shredded cheese.
Bring 1–2 inches of water to a boil in a steamer. Wrap the lid with a cloth to catch condensation.
Lightly grease the molds with oil or butter. Arrange them in the steamer basket and fill each mold about ¾ full with batter.
Steam over medium-low heat until cooked through:12–15 minutes for small molds18–20 minutes for standard moldsThe puto are ready when a toothpick inserted in the center comes out clean.
Place a slice of cheese on top of each puto. Cover and steam 1–2 minutes, just until the cheese softens.
Let cool slightly, then gently remove from the molds. Serve warm.
Notes
Cake flour: This makes the puto softer and lighter. You can use all-purpose flour, but the puto may turn out slightly denser.
Cheese: Use a cheese that melts easily. Brands like Eden or Quickmelt are popular choices. You can also use American cheese or cheddar cheese.
Tips for Best Puto
Do not overmix the batter. Mix just until you no longer see dry flour.
Use medium-low heat when steaming. High heat can make the puto rise unevenly.
Wrap the steamer lid with a cloth. This prevents water from dripping onto the puto.
Fill molds about ¾ full. This gives the puto room to rise.
Storage
Store leftover puto in an airtight container in the refrigerator for up to 3 days.
To reheat, steam for a few minutes or microwave for 15–20 seconds until soft again.