Cut squash and zucchini lengthwise into 1/4-inch-thick slices. Cut bell pepper into 1/2-inch-thick strips.
Grill vegetables, covered with grill lid, over medium-high heat (350° to 400°) 2 to 3 minutes on each side or until tender.
Toss hot vegetables with pesto. Sprinkle with salt and pepper to taste, and serve immediately.
Note: For testing purposes only, we used Buitoni Pesto With Basil.