Heat the ghee in a large skillet over medium-high heat until melted and shimmering.
Add the diced chicken breast to the skillet and sear until golden brown on all sides, then remove and set aside.
In the same skillet, add the diced onion, garlic, and ginger, sautéing until the onion is translucent and fragrant.
Stir in the garam masala, turmeric, sea salt, and black pepper, cooking for 30 seconds to release the oils and aromas.
Pour in the tomato puree and full-fat coconut milk, whisking gently to create a smooth, velvety sauce base.
Return the chicken to the skillet, reduce the heat to low, and simmer for 8-10 minutes until the sauce thickens and the chicken is fully cooked.
Serve the warm butter chicken over the cooked basmati rice and garnish with freshly chopped cilantro.