One of my most favorite dishes, it takes a day, sometimes two but its all worth it.
1. Cut the core from the cabbage and cook in salted water on medium high. Every 5 minutes or so using two forks remove few layers of leaves. When the leaves are cool cut off the hard part in the middle of the leaf.
2. Cook rice, fry mushrooms and 1 onion (separately) and mix all in big bawl or pot.
3. Add ground chicken, salt and pepper and mix all well.
4. Get the roasting pan ready, put few pieces of butter on the bottom of the pan then line it with smaller leaves from the cabbage ( I use the really small ones that are too small for rolling or any that ripped ). In each leaf put some of your rice mixture, fold the sides in and roll, arrange the rolls tight. On top put more little leaves and butter.
I always make more then we can eat for dinner so the extra ones go to freezer.
5. I make mushroom sauce but you can also make tomato. I use 2 cans of cream of mushroom soup, some water and extra mushrooms, heat it up and pour it over the leaves. Bake in 400F for about 40 minutes.