So, even if there are already many tzatziki recipes here, my tzatziki still tastes best (and is also not as powerful as with cream quark, etc.):
Mix the cream cheese, quark and yoghurt well with a whisk until you get a uniform mixture. Mix in the grated snake cucumber with the finely chopped or better grated garlic cloves and season with pepper and a little salt. Smooth with a dash of olive oil and put in a cool place.