For the Beef Tartar with Quail Egg, cut the beef lung roast into small pieces, not too finely, so that the tartar does not become too mushy. Then chill well again.
In the meantime, finely chop the capers, gherkins, anchovy fillets and spring onions. Mix with mustard, Worcestershire sauce and lemon juice and season well with slaz and pepper.
Finally, mix in the beef. Crack the raw quail egg into a small cup without damaging the yolk.
Arrange the Beef Tatar in the middle of a plate (e.g. with the help of a doriol ring), make a small hollow and let the raw quail egg slide down.