Ukranian cabbage rolls are delicious served with sour cream.
Freeze the head of cabbage overnight, and then thaw in the sink in the morning. This will soften the leaves enough for making rolls without boiling the cabbage. Remove the tough outer leaves and set them aside. Cut out the core from the cabbage and separate the whole leaves from the head, placing them in a large bowl. Set the bowl aside.
In a large bowl, combine the rice, salt and pepper. The rice doesnt need to be completely cooked, since the cabbage rolls will be in the oven for a while. That will help give them some room to expand and absorb moisture.
In a small frying pan on medium-low heat, melt the 2 tablespoons of butter. Add the onion and fry until the onion is soft and translucent. Add the onion mixture to the bowl of rice.
In a small saucepan over medium heat, add the tin of tomato soup, the 1/2 cup of butter, and the water.
Cook until the butter is completely melted and the mixture is smooth.
This tomato sauce will be used to spread over each layer of cabbage rolls.
Line the bottom of the roaster pan with a couple of the reserved outer cabbage leaves so that the cabbage rolls dont stick to the bottom.
Discard any extra outer leaves you may have.
To assemble: Set up your cabbage rolling station with the bowl of cabbage leaves, the bowl of rice with a spoon, the tomato sauce with a ladle, the roaster pan, a cutting board and a knife, and a dry towel to rid the cabbage of excess moisture, if necessary.
To roll the cabbage rolls, cut each cabbage leaf in half lengthwise (or leave it whole to make large cabbage rolls), cut off any tough stem remaining on the leaf, and place a tablespoon or two of rice on the bottom of each half. Roll it up while pinching in the sides - if theres a side left exposed, it aint the end of the world. Place the cabbage rolls in the roaster pan so that theyre quite snug, and after you complete a layer of cabbage rolls, ladle on some of the tomato soup mixture.
Continue until you run out of rice and/or cabbage. Top with all of the remaining tomato soup mixture.
Preheat the oven to 350degrees F (180C). Cover the roaster pan with a lid or with tin foil and bake for 1hour, or until the cabbage leaves are tender when they are pricked with a fork.