Knead the mince and mustard. Season with onion powder, salt and pepper. Form two oval meatballs from the mixture and fry them in hot oil while turning for about 10 minutes. Remove from the pan and keep warm.
Fry the vegetables in the cooking fat over a high heat for 4-6 minutes, then continue to fry over a medium heat for 4-6 minutes. Stir several times. Stir in crème fraiche. Arrange the vegetables with the meatballs on a plate.
Sprinkle with parsley.