Add water and salt in the inner pot of instant pot.
When the water is boiled, add 2 tablespoons of unsalted butter and stir continuously.
Close the lid and set the instant pot to medium heat.
Press the “Manual” button and cook for about 10 minutes on HIGH pressure.
Release the pressure naturally through the steam vent and open the lid.
Stir in Parmesan cheese and ½ cup unsalted butter.
Add in salt and black pepper and keep the mixture aside to cool down.
Preheat the oven to 400 degrees F and spread the polenta mixture on the baking dish.
Bake uncovered for 25 minutes till golden brown and cut in squares when done.
Dish out and serve hot.