In a large skillet cook onion and ginger in hot oil until onion is tender. Stir in curry powder and salt; cook and stir for 2 minutes more. Add green beans, yellow summer squash, and 1/4 cup chicken broth. Tear off a 36x18-inch piece of heavy foil. Fold foil in half to make an 18-inch square. Place the curry mixture in the center of the foil. Bring up 2 opposite edges and seal with a double fold. Fold remaining edges to completely enclose the vegetables, leaving space for steam to build. Place foil packet on the grill rack directly over medium heat; grill about 30 minutes or until beans are crisp-tender, turning packet once halfway through grilling. Open foil packet; add tomatoes and stir gently to combine. Serve as above.
Prepare vegetables as directed. Transfer cooked vegetables to a microwave-safe casserole; cool completely. Cover and chill for up to 24 hours. Microwave, covered, on 100% power (high) for 5 to 6 minutes or until heated through, stirring once halfway through cooking. Serve as directed.