Go to the best butcher in town and ask for his best cut of tenderloin/fillet, nicely marbled with some fat. Then ask him for a sliver to taste and keep one eye on the other customers. See them taking a step back when they see you eating raw meat! Back home use your sharpest knife to slice the beef very thinly. Then the slices into strips and finally the strips into very small cubes. Mix all ingredients except the egg yolks, taste and add salt and pepper. Use a serving ring to plate and finish with the egg yolks.