Rinse fish thoroughly in cold water; pat dry. Make a shallow S-shaped slash on each side of fish; sprinkle with salt and pepper. Set aside.
Combine 1/4 cup flour and cornmeal in a medium mixing bowl. Dredge fish in cornmeal mixture; set aside.
Heat 1/4 inch oil in a large skillet to 350°; add fish, and fry 4 minutes on each side or until fish flakes easily when tested with a fork. Drain on paper towels; keep warm.
Drain oil, reserving 3 tablespoons in skillet. Add garlic; cook over medium heat until yellow. Add tomato puree, rosemary, and bay leaves; cover and simmer 12 to 15 minutes.
Combine remaining flour and vinegar: mix well. Stir into tomato sauce; cook, uncovered, over medium heat 2 minutes. Reduce heat to low; add fish, and cook an additional 2 minutes. Discard bay leaves.
Remove fish to a warm serving platter; cover with tomato sauce. Serve immediately.