Roxi found some "Authentic Greek Yogurt" today, the final ingredient for home-made tzaziki sauce.
Here it is, sitting with some other ingredients:

1 1/2 cucumbers were grated and drained.

The recipe called for 3 cloves of garlic, so we naturally used 6.

A little salt, a little mint, and voilá!

Full recipe:
500mg of yogurt
1 cucumber (1.5 was too much)
6 (or more) cloves of garlic
1 teaspoon of salt
1 tablespoon of fresh mint
Instructions:
1) Just mix it all together. (only thing is to be careful to drain the cucumber to avoid the tzaziki being too liquid).
2) Chill, and eat with bread or chips, and your favourite beer.
3) Let your dog lick the yogurt container: