Heat oven to 400° F. Toss the squash, oil, and ¼ teaspoon each salt and pepper on a rimmed baking sheet. Roast, turning once, until tender, 35 to 45 minutes.
Brown the bacon in a large nonstick skillet over medium heat, 6 to 8 minutes; remove and crumble. Reserve the skillet.
Add the eggs to the drippings in the skillet and cook, covered, 2 to 4 minutes for slightly runny yolks. Season with ¼ teaspoon pepper.
Serve the squash with the eggs, bacon, and avocado.