PREHEAT oven to 400ºF. Rinse fish with cold water; pat dry with paper towels. Mix cracker crumbs, 2 Tbsp. of the Parmesan cheese and 1 Tbsp. (3 tsp.) of the basil in pie plate.
SPREAD both sides of fish evenly with 3 Tbsp. of the dressing; coat with crumb mixture. Place on large baking sheet. Add tomatoes, cut-sides up, to baking sheet. Brush tomatoes with remaining 1 Tbsp. dressing; sprinkle with remaining 2 Tbsp. Parmesan cheese and the remaining 1 tsp. basil.
BAKE 12 min. Remove pan from oven. Change oven to Broil setting. Place baking sheet 6 inches from heat source. Broil 2 to 3 min. or until fish and tomatoes are lightly browned.