Step 1

In a 12-inch skillet over medium-high, heat the ghee until shimmering. Add the chicken and cook, stirring only once or twice, until lightly browned, 3 to 5 minutes; the chicken will not be fully cooked. Using a slotted spoon, transfer the chicken to a large plate; set aside. To the fat in the pan, add the chopped chilies; reduce to medium and cook, stirring, until softened, about 2 minutes. Add the cumin, coriander and garam masala; cook, stirring, until fragrant, about 30 seconds. Add the ginger, garlic and tomato paste; cook, stirring, until the paste darkens and sticks to the pan, about 2 minutes.

Step 2

Stir in the grated tomatoes, sugar, ½ teaspoon salt and 1½ teaspoons pepper; bring to a strong simmer over high, scraping up any browned bits. Reduce to medium-low and simmer gently, uncovered and stirring occasionally, until the sauce is thickened and slightly reduced and the fat rises to the surface, 5 to 7 minutes.

Step 3

Stir the chicken and accumulated juices back into the skillet. Bring to a gentle simmer over medium, cover partially and cook, stirring occasionally, until the chicken is no longer pink when cut into with a knife, and a spoon drawn through the mixture leaves a trail, about 5 minutes. Add the yogurt and cook, stirring, until well combined and heated through, 1 to 2 minutes. Off heat, taste and season with salt and pepper. Transfer to a serving dish or serve from the skillet. Sprinkle with the sliced chili and mint; offer lemon wedges on the side.