Combine vinegar, garlic, honey, mustard, salt, onion powder, basil, oregano, red pepper flakes and black pepper in small bowl.
Wisk in vegetable oil and olive oil in thin steady stream until well blended. Or combine all ingredients in jar with tight fitting lid; cover jar and shake until well blended. Store in refrigerator
Citrus Marinade
For marinade, whisk lime juice, oil, green onions, tarragon, garlic powder, salt and pepper in medium bowl Place tuna in large resealable food storage bag; add marinade. Seal bag; turn to coat. Marinate in refrigerator 1 hour, turning occasionally.
Salad
Prepare grill for direct cooking. Drain tuna; discard marinade. Grill 8 to 10 minutes or until tuna begins to flake when tested with fork, turning once. (or broil tuna 4 inches from heat, 8 to 10 minutes, turning once.) Slice tuna into 1/4 inch thick slices; set aside
Bring 2 cups water to a boil in large saucepan over high heat. Add beans; cook 2 minutes. Drain; rinse under cold water.
Place lettuce on large serving platter. Arrange tun, beans, potatoes, tomato, eggs, onions and olives on lettuce. Serve with dressing.