Grilled Tandoori Chicken Skewers

Tandoori Seasoning Blend;
3tbsp tomato purée
2 tbsp coriander
1tsp tamarind paste
1tsp sugar, 1tsp salt
1tbsp vegetable oil
1tbsp garlic powder
1tbsp turmeric, 1/4tsp black pepper
1tbsp ground ginger
1tsp cardamom
1tsp clove, 1tsp cayenne