Heat a few splashes of olive oil into a frying pan. Add onion and cook until softened, add garlic and cook a minute longer. Remove from pan onto a plate.
Add steak to pan and sauté quickly, without cooking completely. Remove from pan and set aside with onions and garlic Pour beef consommé and wine into pan, and mix in Dijon mustard, pepper, salt and nutmeg. Scrape the bits from the bottom of the pan, while mixing well and let simmer a few minutes. Add sour cream without boiling, just warming it up, add beef, onions and garlic. Let
everything heat up together. Serve over cooked rice or noodles.