Kaieser roll with beef hamburger and Truffle ketchup

Grind the beef fillet, and shape an hamburger 1 in thick. Quickly cook it on both sides in a non-stick pan, add salt and pepper.

Toast the Kaiser roll, slice it in two and lay the spinach sprouts, some onion rings, the hamburger, the fontina cheese and the quail egg on one side. Pour plenty of truffle ketchup on top and sprinkle with extra virgin olive oil.