Take a mixing bowl. Add yogurt, gram flour, spice powders and mix well.
Keep 1 tablespoon marinade aside for the chopped bell peppers.
Add chicken pieces to the marinade and mix.
Add ginger garlic paste, minced garlic, lemon juice, salt and mix.
Keep this marinated chicken in refrigerator for 1 to 2 hours or even longer.
Add the chopped bell peppers in the 1 tablespoon marinade which was kept aside, mix and keep in refrigerator.
Light the TTK Prestige barbecue charcoal grill.
Oil the grill plate so that the chicken does not stick to it while getting barbecued.
Carefully thread the marinated chicken pieces onto the skewers in such a way that after ever 2 pieces thread 1 green and 1 red bell pepper piece onto the skewer too.
Place the skewers loaded with chicken and veges on the lighted charcoal barbecue.
Baste the chicken pieces with melted butter.
Cook for 5 minutes on one side and turn to the other. Keep turning the skewers so that chicken gets cooked on all sides.
After chicken is cooked, take it off the grill.
Garnish with coriander leaves and sliced onion and serve hot.