Melt half of the butter in a large saucepan and fry the diced onion in it until glassy.
Dissolve the broth in 1,2l of boiling water and add the mushrooms to the broth so that the aroma is well absorbed into the broth.
Put the rice in the pot and lightly fry in the butter onion mixture.
Then gradually add the mushroom broth until the rice gradually gets a perfect consistency.
When the broth is completely in the pot and the rice has its perfect consistency, add the remaining butter ,about 5 tablespoons of parmesan (you can add more if you wish) and to taste a lot of salt and pepper. Then the risotto is ready to serve and tastes wonderful with a little wild garlic or parsley and parmesan. Good Appetite!