1. Preheat oven to 450°.
2. Cut 4 (18 x 12-inch) rectangles of foil. Place 1 fillet on each sheet.
3. Sprinkle each fillet evenly with Greek seasoning and garlic powder. Layer lemon slices and next 5 ingredients evenly over fillets. Drizzle each fillet with 1 teaspoon olive oil. Fold foil in half over each fillet to form a packet; crimp edges to tightly seal. Place foil packets on a baking sheet.
4. Bake at 450° for 18 minutes or until fish flakes easily when tested with a fork. Remove fish from foil; transfer to plates. Serve immediately.