Clean, rinse, and cut the chicken into cubes.
In a large bowl mix chicken with lemon juice and salt.
Mix it well. Let it marinade for 30 minutes in the refrigerator.
Meanwhile, let's assemble all the ingredients listed under 'The first set of ingredients.' Combine all the above ingredients in a bowl.
Assemble: all the ingredients listed under 'second set of ingredients.' If cilantro, green chilies or garam masala aren't your favorites, then feel free to leave them out. Your tikkas will still turn out good. Combine both the ingredients (the first set of ingredients + the second ingredients) in a large bowl.
Mix it well. Do the taste test.
Add chicken. Rub this marinade onto the chicken. Marinade chicken in this mix for 5-6 hours or overnight.
Preheat oven @400 degree F. Remove chicken from the fridge and thread the pieces onto the skewers. Evenly divide the pieces between 6 skewers.
Cook for 25-30 minutes turning them once in between until cooked through.
Remove from the oven. Generously brush with butter. Transfer the skewers to a platter and serve hot.