Serve this dish with our Green Tomato Salsa.
In a large resealable plastic bag or airtight plastic container, combine oil and lemon juice. Shake well. Add fillets, and toss them gently until coated with marinade. Refrigerate 30 minutes.
Meanwhile, heat a grill or grill pan on medium-high heat. Remove the fish from the marinade. Let excess marinade drip off, and discard. Season with salt and pepper. Grill the fish until browned and cooked through, 2 to 3 minutes per side; serve immediately.