Stir together the water, milk, cornmeal, salt, and pepper in a medium-size saucepan over medium-high heat and bring to a boil, stirring often.
When it begins to boil reduce the heat to low then continue stirring until it begins to thicken, 2 to 3 minutes.
Take off the heat then stir in the butter and Parmesan until well combined.
Season with additional salt & pepper if needed.
