Place chicken in a large bowl. Add lemon juice. Mix. Season with salt. Cover and marinate in the refrigerator for 10 mins.
Meanwhile, place ginger, garlic, cumin seeds, garam masala, ground coriander, red chili powder, red color (if using) and yogurt in a blender, and process to form smooth paste. Add a little water if needed.
Add the ground mixture into the bowl of chicken. Mix. Cover, and marinate for another 30 minutes or overnight if possible.
Preheat grill. Thread chicken pieces onto skewers. Grill for 10-15 minutes or until cooked through.