Okay kiddo, have you ever had yogurt before? Tzatziki is a special kind of yogurt that comes from Greece. It's made with something called "strained yogurt," which is like regular yogurt but thicker and creamier.
To make tzatziki, you mix the strained yogurt with some grated cucumber, garlic, salt, and a little bit of olive oil. Some people also add lemon juice or fresh dill for extra flavor.
The final result is a dip that's perfect for dipping pita bread or veggies into. It's really yummy and refreshing, and it's a great way to try something new from a different part of the world.