This dish is a classic beloved by the people of southern Germany.
Ingredients for the sauce:
Roastbeef Steak, ideally with the fat cap still on
Onions 2 medium
Red wine ~150ml
Beef Stock (can be made with any other stock too) ~150ml
Mustard 1 teaspoon
Cornstarch
Salt to taste
Cook the steak to your liking. While the steak rests in the same pan: sauté the onions for 3-5 minutes until soft, deglaze with wine. Add Mustard and stock, let it cook for 2 min and thicken the sauce with the cornstarch (make a slurry with a little water and one tablespoon of cornstarch in a separate bowl, add it to the sauce and bring it to a boil).
Ingredients for the fried onion topping:
Oil
Onions
Flour
Salt
Cut the onion into rings, cover them in flour then fry in hot oil (~170C). Take out before they look done because they will keep gaining color when you have already taken it out. Put them on a kitchen paper and salt while still hot.
Plate it by putting your steak on and pouring over the sauce, then top with fried onions.
Best served with Käsespätzle (see my account for the recipe) and a quick cucumber salad.
