In a large bowl, combine Greek yogurt, garam masala, smoked paprika, ground cumin, minced garlic, minced ginger, and salt to create a fragrant marinade. Add the boneless chicken thighs, ensuring they are well-coated. Cover and refrigerate for at least 1 hour, preferably overnight.

Heat a generous drizzle of cooking oil in a heavy-bottom skillet over medium-high heat. Once hot, add the marinated chicken thighs in batches, searing for 5–7 minutes on each side until beautifully browned. Remove from skillet and set aside.

Lower heat to medium, and sauté the diced onion for 5 minutes until soft and golden brown. Stir in minced garlic and ginger, ground cumin, and smoked paprika. Cook for 2 minutes to release aromas.

Stir in the tomato puree and bring to a simmer over medium heat. Cook for 5–7 minutes until slightly thickened. Optional: blend until smooth using an immersion blender.

Pour in the heavy cream, stirring well to combine, and add the seared chicken back into the pan. Simmer on low for 15 minutes to let flavors meld.

Remove from heat, garnish with chopped cilantro, and serve hot with basmati rice or naan.