Heat the oven to 350 °F.
Combine the ingredients for the dressing in a bowl, other than the salt and pepper. Whisk until emulsified.
Add salt and pepper to taste.
Chop the squash into large chunks and place in a baking dish. Drizzle with olive oil and sprinkle with salt and pepper.
Roast the squash for 35-40 minutes, until tender.
Remove the squash from the oven, and let it cool. Remove the skin from the squash and cut it into bite-sized cubes.
Steam the asparagus until tender-crisp. It should take 3-4 minutes.
Remove the asparagus to a bowl to cool.
Cut the cherry tomatoes in half.
Cut the avocados into bite-sized chunks.
Place the cooked squash on the bottom of a 9" x 13" casserole tray.
Cover the squash with the asparagus, then cover the asparagus with the avocados and sliced cherry tomatoes.
Drizzle the salad dressing over the vegetables, and serve.