In a large mixing bowl, whisk together the white cornmeal, salt, and sugar until combined.

In a separate bowl, mix the milk, water, and melted butter. Slowly pour the wet ingredients into the dry mixture, stirring continuously to avoid lumps.

Once a soft dough forms, gently knead it with your hands for 2–3 minutes until it becomes smooth and pliable. If the dough feels too dry, add a tablespoon of water at a time until the consistency is right.

Fold in the shredded queso fresco and mozzarella cheese, evenly distributing them throughout the dough.

Divide the dough into 8 equal pieces and roll each into a ball. Flatten each one into a disc about ½ inch thick.

Heat a skillet or saucepan over medium heat and add 1 tablespoon of butter. Once melted, place the arepas in the pan without overcrowding.

Cook for 4–5 minutes on each side, or until golden brown with a slight crisp on the outside and melty cheese inside.

Optional: Cover the pan with a lid for the last minute of cooking to help melt the cheese completely.

Serve warm—ideally with a pat of butter on top or a side of guava jam for a sweet-savory contrast.