3 tablespoons light olive oil or 3 tablespoons canola oil
2 tablespoons red wine vinegar
1 clove garlic, minced
1/2 teaspoon salt
2 tablespoons fresh basil, minced
1/4 teaspoon black pepper
1 (20 ounce) can white kidney beans or great northern beans
1 (13 ounce) can albacore tuna in water, drained and flaked
2 scallions, sliced
1/4 cup red, yellow, or orange sweet bell peppers, chopped
6 leaves bibb lettuce (optional)