Preheat oven (or grill) to 400 degrees F. Grease a large baking sheet or roasting pan (lined with foil) generously with olive oil.
Remove any tough outer leaves from the brussel sprouts and slice them in half, unless you are using baby ones, in that case leave them whole.
Add to a large bowl along with the sweet potatoes, onions, and butternut squash drizzle liberally with olive oil - about 2 tablespoons, add syrup, vinegar, chipotle pepper, & pepper.
Toss the vegetables and adding more olive oil if needed. Spread them out in one layer on the baking sheet.
Bake about 25-30 minutes or until sweet potatoes are tender and brussel sprouts are lightly browned.
Meanwhile cook bacon however you see fit, I like to put it in a separate baking pan and bake it about 12-15 minutes or until crispy. Drain on paper towels and crumble when cool enough to handle.
Once the vegetables are cooked through sprinkle with Parmesan and bacon, toss and serve.