The choice of rice matters here. Instant rice (Minute Rice) works very conveniently in this recipe because it cooks quickly and reliably in the slow cooker environment without becoming gummy. If you prefer to use regular long-grain white rice, reduce the amount to three-quarters of a cup and rinse it very well under cold running water until the water runs clear before adding it — rinsing removes excess surface starch that would otherwise make the dish thick and gummy rather than having the clean, separate grain texture that makes this recipe so satisfying. Do not use brown rice in this recipe without significantly increasing the cooking time, as brown rice requires considerably longer to cook than white rice.
The sugar in the ingredient list is not optional and it is not there for sweetness — it is there to balance the natural acidity of the canned tomatoes, which can taste sharp and one-dimensional without a small amount of sugar to round out and harmonize the flavors. One teaspoon is the right amount: enough to smooth the tomato flavor without making the dish taste sweet. This is a technique used throughout Italian and Eastern European cooking, both of which have deeply influenced the stuffed cabbage roll tradition, and it makes a genuinely noticeable difference in the finished dish.
For the cabbage, a small to medium head of green cabbage is ideal. Do not cut the pieces too small — roughly one-inch chunks hold their shape better through the long cooking time and give the finished dish a more satisfying, hearty texture. Very finely shredded cabbage will essentially dissolve into the sauce during cooking, which produces a completely different texture. Some people prefer this, but most people making this recipe are looking for identifiable pieces of tender cabbage in each bite alongside the beef, rice, and tomato sauce.
