Begin by cutting your boneless chicken thighs or breasts into sizable chunks. In a bowl, combine these pieces with Greek yogurt, Kashmiri red chili powder, salt, and lemon juice. Ensure all the chicken is thoroughly coated. Cover and refrigerate this mixture for at least 8 hours or overnight.

In a large skillet, heat a couple of tablespoons of oil or ghee over medium heat. Once hot, add finely chopped onions along with a pinch of salt. Cook the onions for about 8-10 minutes, stirring occasionally, until they turn golden brown.

Incorporate ginger garlic paste and optional chili. Sauté for 2-3 minutes until fragrant.

Stir in turmeric, garam masala, coriander, and cumin powders. Cook for 1-2 minutes until fragrant. Add chopped tomatoes and cook for about 10 minutes until sauce thickens.

Pour in about one cup of hot water, stirring to combine. Cover and let simmer for 15-20 minutes over low heat.

Grill chicken pieces on medium-high heat for about 5-7 minutes per side, until charred and cooked through.

Stir heavy cream into the simmered sauce, then fold in grilled chicken pieces along with kasuri methi. Cook for an additional 5-7 minutes over low heat.

Transfer to a serving dish, drizzle with extra cream and sprinkle with fresh coriander leaves before serving.