Cut the cauliflower into bite-sized florets and combine with coconut milk, lime juice, and ginger in a bowl. Marinate for at least 15 minutes.

Preheat your oven to 450°F (232°C) or your air fryer to 390°F (199°C).

Drain and toss the cauliflower with arrowroot starch and kosher salt. Bake for 7-10 minutes or air fry for 8-10 minutes.

Heat coconut oil or ghee in a skillet, add onions and sauté until translucent. Stir in garlic and cook until fragrant.

Add garam masala, curry powder, turmeric, and salt, and bloom the spices.

Pour in the reserved coconut milk marinade and canned tomatoes, then simmer for 5-7 minutes.

Transfer the sauce to a blender and blend until smooth, then return to the skillet.

Add the roasted cauliflower to the sauce, stir to coat, and heat through.

Serve the butter cauliflower over rice or cauliflower rice, garnished with cilantro.