Heat oven to 400°F. Place cod fillets in ovenproof casserole.
Stir together oil, garlic, salt and pepper in small dish. Brush or drizzle about two-thirds of mixture over fish. Arrange tomato slices over top; brush or drizzle with remaining oil mixture.
Bake in 400°F oven for 25 minutes or until opaque in center and fish just begins to flake when tested with fork.
Meanwhile, stir together dressing, parsley, lemon juice and capers in small bowl. Serve with cod.