For the chicken marinade, combine the yogurt, lemon juice, garlic, garam masala, Makhir ginger, Sirarakhong chillies, Byadgi chillies, turmeric and salt in a medium bowl or large resealable container, and whisk to combine. Add the chicken and stir to coat, making sure every piece is covered in the marinade. Cover and refrigerate for 6 hours to overnight (for best results, we love a 12 to 24-hour marination period!).

Remove the chicken from the refrigerator before you start making the butter sauce to come to room temperature. To make the gravy, heat 2 tablespoons butter and oil in a large heavy-bottomed pot or Dutch oven over medium heat. Add the coriander, cumin, cloves, and cardamon, stir to coat in the hot fat, and cook until the coriander seeds turn a shade darker, about 30 seconds to 1 minute. Add the onions and cook, stirring occasionally, until the onions have softened and are starting to turn light golden, about 12 to 15 minutes.

While the onions are cooking, preheat the broiler to high, moving the rack to be about 4 to 6 inches from the broiler.

Add the ginger, garlic, and coconut sugar to the softened onions, and continue to cook, stirring occasionally, until the ginger and garlic soften and the onions turn deep golden, about another 4 to 5 minutes. Stir in the Sirarakhong Hathei chillies, garam masala, Byadgi or Kashmiri chillies, turmeric, and cinnamon, and cook until the spices are fragrant, about 45 seconds. Add the tomatoes and their juices and 1 cup water, gently breaking the whole tomatoes up with a spoon, and bring to a simmer. Reduce the heat to medium low and cook, uncovered, until the tomatoes lose their raw flavor and the sauce has reduced slightly, about 20 to 22 minutes.

While the sauce is simmering, cook the chicken. Spread the chicken in a single layer onto a large, rimmed baking sheet. Broil until cooked through and burnished in spots, about 12 to 15 minutes. Remove from the oven and set aside.

Transfer the tomato mixture to a blender, reserving the pot, and let it cool for 10 minutes. Add 2 tablespoons paan methi, cover, and, holding the cover in place with a kitchen towel over it, start blending on low (you don’t want the heat to cause the blender lid to come off!). Once the mixture is looking smooth, stop and add the remaining 3 tablespoons butter, and start blending again, slowly increasing the speed to medium high, and purée until smooth and silky. Taste and adjust salt and sugar, if necessary.

Transfer the blended sauce back to the pot and stir in the reserved chicken and any drippings that have accumulated. Add the heavy whipping cream and crumble in the remaining 1 tablespoon paan methi, and stir to combine, place over medium heat, and bring to a simmer. Cover partially and cook until the chicken is heated through, about 5 to 7 minutes.

To serve, transfer to a shallow serving bowl, drizzle with an extra flourish of heavy whipping cream, if desired, and finish with a sprinkle of chopped cilantro. Enjoy with naan for scooping up all that deliciousness!