In a bowl, combine the Greek yogurt, garam masala, turmeric, cumin, sea salt, and black pepper.
Cut the chicken breast into bite-sized pieces and toss in the yogurt mixture to coat; let marinate for at least 15 minutes.
Prepare the basmati rice according to package instructions so you have 0.5 cup of cooked rice ready for serving.
Heat the ghee in a large skillet over medium-high heat. Add the marinated chicken and sear until browned on all sides, then remove and set aside.
In the same skillet, add the diced yellow onion and sauté until translucent, about 5 minutes.
Stir in the minced garlic and grated ginger, cooking for 1 minute until fragrant.
Pour in the tomato puree and bring to a gentle simmer. Return the chicken to the pan and cook for 5-7 minutes until the chicken is cooked through.
Stir in the coconut milk to create a creamy sauce and adjust seasoning if necessary.
Serve the chicken tikka masala over the warm basmati rice and garnish with fresh chopped cilantro.