Dice the chicken breast into bite-sized 1-inch cubes and season with sea salt and black pepper.
Heat the ghee in a large skillet over medium-high heat. Add the chicken and sear until golden brown on all sides, then remove from the pan and set aside.
In the same skillet, add the finely diced yellow onion and sauté for 3-4 minutes until translucent.
Stir in the minced garlic and grated fresh ginger, cooking for 1 minute until fragrant.
Add the garam masala, turmeric, and ground cumin to the aromatics, stirring constantly for 30 seconds to toast the spices.
Pour in the tomato puree and return the chicken to the skillet. Lower the heat and simmer for 5-7 minutes until the chicken is cooked through.
Stir in the full-fat coconut milk to create a rich, creamy sauce and simmer for another 2 minutes.
While the chicken simmers, steam the cauliflower rice in a separate pan with a splash of water until tender.
Serve the butter chicken over the cauliflower rice and garnish with freshly chopped cilantro.