In a large stockpot, heat the fat over medium heat. Add the lamb meat and brown. Once the meat is brown remove and reserve. Reduce the heat to low and add the onion, garlic, and diced vegetables. Season with salt and pepper, and sweat for 5 minutes. Return the reserved browned meat and then add the tomatoes and paprika and simmer for 10 minutes.
Add stock and simmer for 3 hours until lamb is tender. Add the cooked beans and check seasoning. Place in bowls and garnish with a tablespoon of sour cream and sliced scallions.