1Prep the chicken: cut it into pieces and add it to a bowl.
2Grate in your chili, garlic and lemon zest.
3Spoon in yogurt, season with salt, pepper and oregano, and leave to marinade for 30 minutes.
4Make the tzatziki: add chopped mint and lemon juice to yogurt. Season generously, then add your grated cucumber. Make sure you squeeze the cucumber gratings to remove moisture. Mix and set aside.
5Dice the tomatoes, removing the stems and add them to a bowl with oregano, salt, pepper, and olive oil. Mix and leave to chill.
6Slice up some iceberg lettuce.
7Cook the chicken in a grill pan or frying pan on a high heat until brown and charred.
8Assemble the gyros: add a big dollop of tzatziki to a warm pitta bread, then add your lettuce, tomatoes and chicken. Top with more tzatziki.