Preheat oven to 375 degrees.
In an oil-coated 9x13 inch baking pan, place fish fillets. Sprinkle lemon juice over fish.
Spread onion, garlic, and spinach across the top of fillets. Sprinkle on dill, nutmeg and salt, and pepper.
Drizzle ghee over top and cover with tin foil.
Bake for 20 minutes until fillets easily flake with a fork. Serve warm.