1. Cut the meat into cubes about 2cm (3/4 in.)
2. Peel and crush the garlic. Put the garlic, curry powder, oil and a little salt and pepper into a bowl and mix well.
3. Add the meat into the bowl and stir well. Cover the bowl with plastic foodwrap and leave it for 30 minutes.
4. Put the wooden sticks into a bowl of cold water and leave them to soak. This stops them from burning under the grill.
5. Shread the lettuce by cutting across it and put it in a bowl. If you are using fresh mint, chop the leaves finely.
6. Cut the cucumber in half, then slice it finely. Mix the lettuce, yogurt, mint and cucumber with a little salt and pepper.
7. Turn your grill on to medium. Dry the kebab sticks on a paper towel, then push the cubes of lamb onto them.
8. Put the kebabs onto the grill rack and push it under your grill. Cook the kebabs for five minutes, then turn them over.
9. Cook the kebabs for 5 minutes more. While they are cooking, cut the pitta breads in half across the middle.
10. Put the kebabs on a plate. Put the pittas under the grill for two minutes but turn off the heat. This will warm them through.
11. Run the tip of a knife along the cut edge of each pitta to open it up. Fill each one with some of the lettuce mixture.
12. Hold a kebab stick at one end and use a fork to slide the lamb off. Put some lamb into each pitta and eat immediately.