Preheat oven to 450°F. Line a baking tray with foil (or grease the baking sheet).
Rinse fish and with paper towels, pat dry inside and out.
Score the top of each fish three times.
Brush both the inside and outside of the fish with oil and arrange on the baking sheet.
Mix together garlic and turmeric, and spread the inside of each fish with ¼ of the mixture. Sprinkle the inside of each fish with 1 teaspoon of Italian dressing mix (or Italian seasoning, salt, and pepper).
Add 3 slices of lemon and 1 sprig of rosemary to the inside of each fish.
Sprinkle the outside of each fish with ¼ teaspoon each of garlic powder, salt, and pepper.
Bake for 15-20 minutes, or until the internal temperature of the fish reaches 145°F.
Optional step for crispy skin: Move baking sheet to the top rack, and turn oven up to broil. Broil for 2 (or more) minutes to reach desired crispiness, and remove from the oven quickly. Watch it carefully!