Preheat the oven to 425 degrees F. Line a large baking sheet with parchment paper or foil for easy cleanup.
Place the trimmed Brussels sprouts & squash on the prepared sheet pan. Drizzle with the marinade.
Using your hands or a set of tongs, toss to coat the veggies in the marinade, then arrange in an even layer on the sheet pan. Nuzzle the sausage onto the sheet pan, doing your best to ensure everything is in a single, even layer. If needed, use 2 sheet pans to avoid overcrowding.
Transfer the sheet pan to the oven. Roast for 25 minutes, flipping the veggies & sausage halfway through. When cooking has completed, remove from oven & enjoy!