Grate one hundred grams of cottage cheese and cut the remaining into one-and-a-half- inch cubes. Slice each cube into three layers without cutting through. In a bowl, mix together the khoya, saffron and salt.
In another bowl, mix together the grated cottage cheese, chilli powder and salt. Take a cottage cheese cube; spread the green chutney over the first layer, the khoya mixture on the second layer and the cottage cheese mixture on the third layer.
Mix together the yogurt, gram flour, ginger-garlic paste, fresh coriander, green chilies, white pepper powder and lemon juice in a deep bowl.
Add the stuffed cottage cheese cubes and mix gently so that all the cubes are evenly coated with the marinade. Set aside for about an hour.
Thread the cottage cheese cubes a little apart onto skewers and roast in a Tandoor or over a charcoal grill over a moderate heat for five to six minutes, basting them with melted butter once in between.