Bring the water and salt to a boil in a large pot.
Slowly whisk in the polenta, reduce the heat to low, and cook, stirring frequently, for about 30 minutes, or until the polenta is creamy and all the water has been absorbed.
Remove from the heat and stir in the butter and Parmesan cheese.
Pour the polenta into a greased baking dish and smooth the top with a spatula.
Allow the polenta to cool and solidify for about 2 hours.
Cut the polenta into squares, rectangles, or rounds and fry in a hot pan with a bit of oil until golden and crispy.
Notes
Stir the polenta continuously while cooking to prevent lumps.
Polenta thickens as it cools, so if it's too thick, add a bit more water or broth.
If your polenta is too thin, continue cooking it uncovered on low heat until it thickens.
Don't skimp on the salt. It's essential for bringing out the corn flavor in the polenta.
Let the polenta cool a bit before cutting it into shapes for frying. This helps it hold its shape better.