boneless, skinless chicken breast or thighs, sliced into strips (about 500 grams), plain yogurt, milk (60 ml), Shawarma spice mix, Salt, black pepper, cayenne pepper, paprika, Garlic powder and onion powder, ground cardamom and pinch of cinnamon, lemon, Vinegar, small clove garlic, 1 small onion, 1 small tomato, and 1 small green bell pepper, all finely chopped, ketchup or tomato paste, butter or oil