Heat the water, milk and salt in a saucepan over medium high heat. When it is steaming, slowly pour in the cornmeal while whisking the mixture in the pan.
Bring to a boil. Reduce the heat to a simmer and continue stirring occasionally over the next 10-15 minutes while the mixture thickens.
Remove the thickened polenta from the stove and add the butter and the cheese. Stir until smooth and creamy. Taste, adjust the salt if needed and serve warm. Enjoy!
Notes
If you are making this in advance, cover and refrigerate. Reheat in the microwave, about 4-5 minutes on high. Stir vigorously to fluff after reheating.