1/4 teaspoon salt
1/4 teaspoon black pepper
2 small zucchini, halved lengthwise
2 small yellow squash, halved lengthwise
2 plum tomatoes, halved lengthwise
2 tablespoons red wine vinegar
2 teaspoons bottled minced garlic
1 tablespoon commercial pesto
Combine 1/4 teaspoon salt, 1/4 teaspoon pepper, zucchini, squash, tomatoes, vinegar, and garlic in a large zip-top plastic bag. Seal and shake to coat. Place the zucchini and yellow squash on grill rack or broiler pan coated with cooking spray; cook 3 minutes on each side or until tender. Place the tomato and onions on grill rack or broiler pan; cook 2 minutes or just until tender.
Coarsely chop the vegetables, and place in a bowl. Add pesto; stir gently.