Slice mushrooms such as button and king oyster mushrooms thinly.
Finely chop onion and garlic.
Heat olive oil in a pan and sauté garlic and onion.
Add mushrooms and stir-fry.
Add cooked rice or cooked grains and stir-fry together.
Pour in heavy cream and tomato sauce.
Season with salt and pepper.
Cook over medium-low heat until ingredients are well mixed.
Finish by sprinkling Parmesan cheese and parsley.