Don't toss that broccoli stem—spiralize it!
Preheat the oven to 425°. Place the sausages in a baking dish. Bake until cooked through, 20 to 25 minutes. Let rest for 5 minutes. Slice on an angle into 1/2-inch-thick pieces.
In a medium saucepan, bring the quinoa and 1 cup water to a boil. Reduce heat to medium-low. Cover and simmer until tender, about 15 minutes.
In a large skillet, heat the oil over medium-high. When the oil begins to shimmer, add the broccoli florets and noodles, stock, garlic, and crushed red pepper; season with sea salt and black pepper. Cook, tossing often, until the broccoli florets are crisp-tender, about 5 minutes. If the pan looks dry, add more stock. Add the sausages and the juices from the baking dish and toss again.
Divide the quinoa between 2 plates. Top with the sausage, vegetables, and Parm, if using.