In a small bowl, whisk together the Greek yogurt, lemon juice, half of the garam masala, and all of the turmeric.
Cut the chicken breast into bite-sized pieces, toss with the yogurt mixture until well-coated, and let marinate for at least 20 minutes.
Heat the ghee in a large skillet over medium heat and sauté the diced yellow onion until it becomes translucent and soft.
Add the grated fresh ginger, minced garlic, and the remaining garam masala to the skillet, stirring for 1 minute until fragrant.
Place the marinated chicken into the skillet and brown the pieces on all sides for about 5 minutes.
Pour in the tomato puree, reduce heat to low, and simmer for 10 minutes until the chicken is cooked through and the sauce has thickened.
Stir in the coconut milk, sea salt, and black pepper, allowing the sauce to become creamy and heated through.
Serve the warm chicken tikka masala over the cooked basmati rice and garnish with freshly chopped cilantro.