MIX first 4 ingredients until well blended. Stir in 1 Tbsp. basil. Mix 2 Tbsp. dressing mixture with remaining basil, tomatoes, onions and cheese; set aside. Pour remaining dressing mixture over tuna in shallow dish; turn to coat both sides. Cover; refrigerate 30 min. to 1 hour to marinate.
HEAT greased grill to medium-high heat. Remove tuna from marinade; discard marinade. Grill tuna 5 to 7 min. on each side or until tuna flakes easily with fork.
SERVE topped with tomato mixture.
Dry white wine
Good Seasons Zesty Italian Dressing Mix
Athenos Traditional Crumbled Feta cheese