Paneer tikka barbeque

Name: Paneer tikka barbeque
Ingredients: 250 gram paneer or Indian cottage cheese; 1 pineapple diced; 1/2 cup medium sized onion(diced); 1/2 capsicum or medium bell pepper (diced); 200 gm yoghurt/ hung curd; 1 tsp ginger garlic paste; 1/2 tsp kashmiri red chilli powder; 2 tsp Kasuri methi; 1/2 tsp turmeric Powder; 1 Tsp coriander powder; 1 Tsp garam masala powder; 1 Tsp chat masala; 1 Tsp ajwain(carom seeds); 1/2 tsp black pepper powder; 1 tbsp lemon juice(optional); 2 tbsp mustard oil (heated); 1/2 tsp black salt; to taste Salt; as needed mustard oil for brushing