Trim excess fat from chicken thighs and cut into 1" strips. In a bowl combine yogurt, ginger-garlic paste, garam masala, ground cumin, ground coriander, turmeric, red chili powder, lemon juice, salt and mustard oil. Add chicken, mix thoroughly so every piece is coated. Cover and refrigerate for at least 1 hour, preferably 3–4 hours or overnight for best flavor.

If using skewers or oven: preheat oven to 220°C (425°F) and thread pieces on skewers or place on a lined baking sheet. If using a stovetop: heat a heavy skillet or grill pan over medium-high heat and add a little oil.

Cook the chicken: Grill, broil, or pan-sear the marinated chicken until edges are charred and internal temperature reaches 74°C (165°F), about 10–12 minutes depending on thickness, turning once or twice. Remove and rest 5 minutes, then chop coarsely into bite-sized pieces.

Onion-Tomato Filling & Sauce

Heat 2 tbs oil or ghee in a skillet over medium heat. Add the thinly sliced onion and sauté until translucent and starting to brown, about 6–8 minutes.

Add the ginger-garlic paste and sauté 30–45 seconds until fragrant. Add the sliced green bell pepper and cook 2–3 minutes until slightly softened.

Add the chopped tomato, tomato ketchup or puree, red chili powder, coriander powder, amchur or kasuri methi and salt. Cook until tomato breaks down and the mixture thickens into a saucy consistency, about 4–6 minutes. Taste and adjust seasoning.

Add the cooked chicken pieces to the skillet and toss to coat in the sauce. Cook together 2–3 minutes to marry flavors. Remove from heat and keep warm.

Mint-Coriander Chutney

Combine mint, coriander leaves, green chili, lemon juice, salt and 2 tbs water in a blender. Blend to a smooth chutney. Add a tablespoon more water if needed to reach a spreadable consistency. Taste and adjust salt or lemon.

Assembling & Serving

Warm the tortillas/rotis: Heat a flat skillet over medium heat. Brush each side of a tortilla or roti lightly with butter and warm 20–30 seconds per side until pliable and slightly golden.

Spread 1 tbs mint-coriander chutney down the center of each warmed tortilla. Place a layer of shredded lettuce or cabbage, then spoon 3–4 tbs of the chicken tikka and onion-tomato mixture on top.

Top with pickled or sliced raw onions, a squeeze of lemon, and a sprinkle of chaat masala if using. Fold or roll tightly into a kathi-style roll, folding in the sides as you roll to secure the filling.

Optional crisp finish: Brush the outside of the roll with a little butter and warm briefly on the skillet seam-side down to seal and develop a light crust, about 30–45 seconds.

Serve immediately with extra chutney and lemon wedges.