Rouladen are traditional German beef rolls filled with mustard, onions, and pickles, and cooked until tender in a rich gravy.
Steps:
1. Pound the beef slices to flatten them. Spread mustard on each slice and top with onions and pickles. Roll up and secure with toothpicks.
2. Brown the beef rolls in hot oil. Remove from the pan and sauté onions. Add the beef rolls back to the pan, pour in beef broth and red wine, and let simmer.
3. Serve the Rouladen with the gravy, boiled potatoes, and red cabbage. Enjoy!