For the polenta with mushrooms and herbs, clean the mushrooms and cut them into small cubes. Boil the butter, water, milk, garlic, salt and pepper, add the corn flour in a stream and cook on a low fire for 30 to 40 minutes to a polenta.
At the end, season and add the mushrooms, the chopped parsley and the whipped cream. Bring the mushroom polenta briefly to the boil and mix well with a wooden spatula. It should be viscous. If necessary, add a little more soup.
Serve the polenta with mushrooms and herbs while still warm.