Rigatoni with Roasted Broccoli and Red Onions

Position racks to divide the oven in thirds. Heat oven to 425 °F. On a large rimmed baking sheet, toss the garlic, broccoli, onion, oil, and 1/4 tsp each salt and pepper and roast until golden brown and tender, 20 to 25 minutes. Arrange the bacon on a second rimmed baking sheet and roast along with the vegetables until crisp, 12 to 15 minutes. Transfer to a paper towel–lined plate. Break into pieces when cool. Meanwhile, cook the pasta according to package directions. Reserve 3/4 cup of the cooking water, drain the pasta and return it to the pot. Add 1/2 cup of the reserved cooking liquid, sprinkle with 1/4 cup Parmesan and toss to coat (add more cooking liquid if the pasta seems dry). Add the roasted vegetable mixture and bacon to the pasta and toss to combine. Serve with the remaining Parmesan.