Cut the chicken breast into 1-inch bite-sized pieces.
Heat the ghee in a large skillet over medium-high heat.
Add the chicken to the skillet and sear until golden brown on all sides, approximately 5 minutes.
Remove the chicken from the pan and set it aside on a plate.
In the same pan, add the diced yellow onion and sauté until translucent and soft.
Stir in the minced garlic, grated ginger, garam masala, and turmeric, cooking for 1 minute until highly fragrant.
Pour in the tomato puree and coconut milk, stirring well to combine the spices into the liquid.
Return the chicken and any accumulated juices to the pan, then simmer for 8-10 minutes until the sauce thickens and chicken is cooked through.
Fold in the fresh baby spinach and stir until just wilted.
Season with sea salt and black pepper, then garnish with chopped fresh cilantro before serving.