Sprinkle salt and pepper on each slice of beef. Spread a thin layer of mustard on each slice. Put a small amount each of the chopped onion, pickles, and pork on one end of the beef. Roll up the beef starting with the end with the filling. Try to tuck in the sides while rolling to help keep the filling from coming out of the sides. Tie the Rouladen using kitchen twine or thick unwaxed dental floss. Be sure to tie the ends tightly to keep the filling inside.

Brown the Rouladen on all sides in a hot frying pan or braiser using a little oil and butter. Once the meat is browned, pour 1 cup of beef broth into the pan and put a lid on the pan. Turn the heat to low and simmer, covered, for 1½ hours. Take the Rouladen out of the pan and remove the strings. Add 1 packet of Swanson® Beef FlavorBoost™ or bouillon to the pan and stir to combine with the gravy. Stir about 1 teaspoon of cornstarch to ½ cup beef broth. Add cornstarch mixture a little at a time to slightly thicken gravy. Cook gravy for a few minutes then pour into gravy dish to serve with the Rouladen.

Serve Rouladen with potato dumplings, mashed potatoes, or spätzle. Red cabbage, green beans, or a cucumber salad are also good side dishes.