Peel the onions, cut each onion in half with a knife, then pour over the slicer.
Heat the clarified butter in a saucepan, fry the onion rings in it, stirring constantly. Pull the pot to one side, sprinkle the flour over it, stir into the onions with a mixing spoon, deglaze with the beef stock and bring to the boil.
Now add the dark soy sauce, tomato paste, ground coriander and red wine to the sauce and slowly simmer for about 10–12 minutes, lightly covered.
Finally, if necessary, season with salt and pepper from the mill.
This spicy onion sauce goes well with steaks, grilled dishes and very well with mashed potatoes, boiled potatoes and pasta.