1. Place squash halves in a large Dutch oven with about 1 inch of water. Bring to boiling. Cook, covered, for 15 to 20 minutes or until tender.
2. Meanwhile, in a saucepan cook lima beans according to package directions, adding kidney beans during the last 3 minutes of cooking; drain and return to pan. Stir in roasted red peppers and salt; heat through.
3. Meanwhile, for vinaigrette,* in a screw-top jar combine vinegar, oil, honey mustard, and garlic. Cover and shake well. Pour over warm bean mixture; toss to coat.
4. Use a fork to scrape the squash pulp from the shells in strands; return strands to each shell. Spoon warm bean mixture atop squash strands in shells, drizzling any excess vinaigrette on top. If desired, sprinkle with freshly ground pepper. To serve, cut each squash shell in half.