– 2 tablespoons unsalted butter divided – 1/2 large onion sliced – 2 tomatoes diced – 1 cup tomato paste – 1/2 head cabbage roughly chopped – 1 carrot cut into large chunks – 1 large potato peeled and cut into large chunks – 6 cups beef broth – 12 oz beef sausage cut into strips – 2 tablespoons all-purpose flour – 1 cup water – salt to taste – ground black pepper to taste