In a large bowl, combine the first 6 ingredients (tomatoes through lime juice) along with half of the salt and the olive oil for slaw; blend well and set aside.
Season fish fillets evenly with remaining salt, pepper and onion powder.
Melt the ghee (or coconut oil) in a large skillet over medium-high heat; add fillets and cook for 3 to 5 minutes per side or until fish flakes easily when tested with a fork.
Serve topped with slaw and enjoy!