In a large pot, bring well-salted water to a boil—this will soften the cabbage, making it easier to work with. While the water heats, cut out the core from the cabbage. Submerge the cabbage in the boiling water and cook until the leaves begin to separate easily. Remove the leaves as they loosen, setting them aside on a plate. Trim the thick stems and cut the leaves to the desired size based on the size of the cabbage rolls you want to make. For larger rolls, use a full leaf; for smaller rolls, halve the leaves. Set the prepared cabbage leaves aside.
In two large bowls, combine the ground meats. In a saucepan, sauté the chopped onion over medium heat, allowing the onions to release moisture and sweat without burning. Add paprika, stirring for a few minutes until it releases a smoky aroma. Remove from heat and add the onions to the meat mixture. Stir in the cauliflower rice, salt, and pepper, mixing everything thoroughly. Your meat mixture is now ready to be rolled in the prepared cabbage leaves.
Place a cabbage leaf in one hand, and spoon some of the meat mixture onto the leaf. Roll the leaf around the meat lengthwise, tucking in the ends to ensure the filling stays secure during cooking. Repeat this process with the remaining meat and cabbage leaves.
To cook, place half a jar of sauerkraut at the bottom of a large pot. Arrange the cabbage rolls on top, then cover them with the remaining sauerkraut. Add enough water to fully submerge the rolls. If desired, tie a bunch of fresh dill and place it in the pot for added flavor. Bring to a boil, then simmer until cooked through. Alternatively, cabbage rolls can be frozen for up to three months.
