This classic German recipe can be made with venison, lamb, mutton, or pork instead of beef. Sauerbraten is one of the best known German dishes and has many regional variations. This recipe is from the Rhineland region of Germany.
Place the vinegar, water, bay leaves, cloves, celery, carrots, quartered onion, salt and pepper in large container (earthenware, glass, plastic, or enamel). Add meat and buttermilk and refrigerate for 4 days.
Take meat out of marinade, and pat the meat dry with a towel. Reserve marinating liquid.
In large saute pan, add chopped onion to the olive oil and brown meat on all sides. After browning, deglaze pan with red wine and add marinade and beef shoulder. Cook until tender, about 1 hour.
Remove the meat from the pan, let rest for 10 to 15 minutes then slice.
Strain marinade and set aside.
Add the butter to the pan over low heat and when melted add the flour. Whisk until it comes together and bubbles. Slowly add the strained marinade stirring constantly until sauce has thickened. Add gravy flavoring and salt and white pepper.
Add brown sugar, to taste, until it is sweet and sour. Stir in the raisins.
Pour sauce over sliced sauerbraten, and serve with red cabbage, potato dumplings, Spatzle, boiled potatoes, or pasta, if desired.