Seitan shawarma with tahini sauce recipe on Second Nature

Name: Seitan shawarma with tahini sauce recipe on Second Nature
Cuisine: Middle Eastern
Ingredients: 400g; seitan, homemade or store bought; 2-4 tbsp; extra virgin olive oil; cumin; coriander powder; paprika; cayenne pepper; turmeric; 1/2 lemon; juiced; 4 cloves; garlic, minced; salt; lemon, juiced; 125ml; cold water, more if needed; 3-4; tomatoes, sliced; 1 small; cucumber, sliced; red onion, finely sliced; 2 small; little gem lettuce heads, shredded; wholemeal wraps; tahini paste