Peel the cucumber and grate it with a coarse grater. Place the grated cucumber in a sieve and press out as much liquid as possible (If it’s too watery, your tzatziki will turn out thin.).
In a bowl, mix together the cucumber, yogurt, garlic, dill, and a pinch of salt and pepper.
Chill the tzatziki in the refrigerator for at least 2 hours before serving.
Cut the pita bread into wedges and warm them in the oven.
Serve the tzatziki with the pita bread.
Tips
Sometimes I remove the watery center with seeds from the cucumber before grating. That helps with moisture, you might want to use a larger piece of cucumber when you do this.