Heat oven to 400 degrees F. Spread zucchini, yellow squash, bell pepper, onion, and garlic in jelly roll pan, 15 1/2 x 10 1/2 x 1 inch. Spray vegetables with cooking spray. Sprinkle with salt and red pepper.
Bake for 30 minutes, turning vegetables once, until the vegetables are tender and lightly browned.
Place vegetables in blender/food processor. Cover and blend on high speed about 1 minute, stopping blender occasionally to scrape sides, until smooth.
Serve warm, or refrigerate at least 2 hours until chilled. Serve with Baked Pita Crisps or Dippers.
To make Baked Pita Crisps, heat oven to 375 degrees F. Split each pita bread around edge with knife to make 2 rounds. Lightly brush oil over pita rounds. Sprinkle with basil and cheese. Cut each round into 8 wedges. Place in single layer in 2 ungreased jelly roll pans, 15 1/2 x 10 1/2 x1 inch, or on 2 cookie sheets. Bake uncovered 6 to 8 minutes or until light brown and crisp. Cool slightly (chips will continue to crisp as they cool). Serve warm or cool. Store in tightly covered container up to 3 weeks at room temperature.