I'm going to try to cook this in the crock pot. I always do it in the oven, but it should work for the crockpot. I love stuffed cabbage but boiling, cutting the leaves off the head, trimming the leaves, and rolling is a PITA so I do it this way to make it easy on myself.

Mix together ground beef, uncooked rice, an egg, salt & pepper, and a squirt of ketchup (optional). Form into meatballs smaller than the size of golf balls.
In the bottom of the crockpot, place a couple whole outer leaves of cabbage to protect the rest from getting scorched. Next a layer of cut up raw cabbage cut into approx. 1 1/2 inch size pieces. Now a layer of meatballs. Pour on some crushed canned tomatoes. Then another layer of chopped cabbage. Continue layers until you run out of meatballs and cabbage. Make sure to top the whole thing with more canned tomatoes and place a few whole leaves on top. Cover and cook for a few hours on med/high.