Cut steaks into strips measuring 3 to 4 inches wide. On a floured surface, coat steak strips with flour. Using a meat mallet, pound meat until thin, approximately 1/8 inches (be careful not to pound holes in the meat).
Season each steak strip with salt and pepper. Put a little chopped onion and 1/4 bacon slice onto the top of each steak strip.
To make rouladen, roll up (jelly-roll style) and tie well with cooking string. NOTE: Cooking string can be found in most supermarkets.
In a large frying pan over medium-high heat, heat vegetable oil. Add a rouladens and brown thoroughly on all sides, turning as necessary. As each roulade is browned, remove from frying pan and transfer onto a large plate.
When all the rouladens are browned and removed from the pan, add wine to the pan drippings and let simmer 1 minute (scraping up any browned bits on the bottom of the pan into the wine).
In a large heavy baking pot or Dutch oven, place the rouladens and cover with the wine mixture; add water to just cover the rouladens. Simmer gently 2 hours or until tender.
When I am make an extremely large batch or rouladen (which is most of the time), I bake them in the oven, covered with the wine mixture, until done. Bake at 350 degrees F. for approximately 2 1/2 hours or until tender when pierced with a fork.
When done, remove from heat and let cool. When cool, remove all the strings and place the roulades back into the wine mixture. At this point, refrigerate the rouladen in the wine mixture. This is an important step, as the rouladens gain more flavor if left sitting in the liquid for one day.
When ready to serve, place the rouladens, with the liquid, back in the oven or on the stove. Using medium to medium low heat, gently reheat the rouladens. Once heated and ready to serve, remove the rouladens from the liquid and place on a large platter.
Make the gravy: Add enough flour to thicken. Cook over medium heat, stirring constantly, until the mixture is thickened and bubbly, about 10 to 15 minutes. Season to taste with additional salt and pepper. Remove gravy from heat and transfer into a large serving bowl. Serve with the rouladens and enjoy!
Makes 6 to 8 servings.
* You can also substitute flank steak.
German Beef Rouladen - King of Meats Recipe: https://whatscookingamerica.net/Beef/GermanRoulades.htm