Preheat oven to 400°F.
Season fish with salt and pepper and place in oven-proof baking dish.
In a food processor, pulse basil, garlic, shallot, salt and pepper a few time until combined. Slowly add in melted butter, cream and lemon juice until well combined. Spread mixture on top of fish evenly.
Bake, uncovered, for 15-20 minutes, until fish is cooked through (if you are using individual fillets, this will take less time).
Garnish with more basil and lemon wedges, and spoon additional sauce over fish to serve.