Rinse the pork schnitzel under running water and pat dry, cut into strips. Peel off the garlic, press through the press and add to the meat together with oil and gyros spice, stir well and marinate for 2-3 hours.
Sear the meat in portions in a pan on all sides and place in a large dish. Pour the cream over the meat, cover the pan and leave to stand in a cool place overnight.
Peel, halve and slice the onions. Clean the peppers and cut into strips. Braise both in oil. Add the onion soup powder and water, bring to a boil and cook for about 10 minutes. Add the gypsy or chili sauce, processed cheese and the marinated meat to the soup and bring to the boil while stirring. Simmer until the cheese has melted. Season to taste with salt, pepper and thyme.
If you want to save time, you can also buy marinated gyros from the butcher, skip the first two steps and start with searing the meat.