Mix the sour cream, curry ketchup and cream together and stir until smooth with a whisk. Season a little with curry powder. Cut the onions into fine rings. Wash the pork tenderloin, pat dry and cut into medallions 2 cm thick.
Briefly fry the medallions in oil in portions on each side, then remove and season with salt and pepper. Then fry the bacon until crispy. Also fry the onion rings in the frying fat and season with salt and pepper.
Put the pork tenderloin, bacon and onion rings in a baking dish and pour the sour sauce over them. Bake in the preheated oven at 200 ° C top / bottom heat for about 30 minutes.
Baguette or rice or mashed potatoes and a fresh salad go well with this.