I make this in my roaster oven. You could also use a crock-pot on HIGH. As the meat's already cooked, basically you just need to let the flavors blend.
2 cups cubed cooked roast beef
2 medium onions, chopped
2 small bell peppers, cut into thin strips
1/2 cup beef broth
2 tsp paprika
1/2 tsp caraway seed
1/2 tsp marjoram
1 can (14 oz) diced tomatoes
salt and pepper to taste
Cook in 4 or 6-qt roaster oven at 200 to 225 for one hour.
Serve over noodles or spaetzle.