Place the salmon fillets on a cutting board and, using a sharp knife, cut them into roughly 2 inch cubes. Try to keep the pieces a similar size so they cook evenly. If you prefer chunkier salmon tikka, feel free to cut slightly larger pieces. Just remember they may need an extra minute or two in the air fryer.
Lightly warm the mustard oil and add it to a large bowl. Add all powdered spices and using a whisk, mix well(helps wake up the spices!)
To it, add yogurt, lemon juice, kasuri methi and ginger garlic pastes. Whisk everything very well to make a smooth tandoori marinade.
In a large mixing bowl, add all of the tandoori marinade ingredients and whisk until you have a smooth, creamy tandoori marinade with no lumps. The marinade should be thick enough to cling to the salmon without sliding off.
Add the salmon pieces to the bowl and gently toss them with a spatula or your hands until every piece is evenly coated. Be gentle, as salmon is delicate and can break apart if handled too much. Let the salmon marinate for 10 to 15 minutes. Since salmon is naturally tender, it doesn't need a long marinating time to absorb all those wonderful flavors.
Arrange the marinated salmon in a single layer in your air fryer basket, leaving a little space between each piece so the hot air can circulate properly. If you're using skin on salmon, place the pieces skin side down. Lightly spray or brush the tops with oil to help the edges develop that beautiful lightly charred finish.
Air fry at 390°F for 8 to 10 minutes, carefully flipping the salmon halfway through cooking. The exact cooking time will depend on the thickness of your salmon pieces and your air fryer model. The salmon is ready when it flakes easily with a fork, stays juicy in the center, and develops lightly charred edges.
Sprinkle some chaat masala & chopped cilantro on salmon tikka before serving!