Bring a pot of salted water to a boil. Add the pasta and cook as the label directs. Meanwhile, heat the olive oil in a large skillet over medium heat. Add the sausage and cook, breaking it up with a wooden spoon, until it begins to brown, about 3 minutes. Add the spring onions/scallions and cook until softened, about 3 more minutes. Add the garlic, mushrooms, salt and pepper to taste; cook, stirring occasionally, until the mushrooms start to brown, about 3 minutes. Add the cherry tomatoes and peas and cook until they soften slightly, about 3 more minutes.
Reserve 1 cup of the pasta cooking water, then drain the pasta. Add the chicken broth to the skillet and cook, stirring, 1 minute. Stir in the pasta (I did not use the full pound of pasta) and cheese, adding some of the reserved cooking water to loosen, if necessary (I did not need to use any of the pasta water). Season with salt and pepper. Drizzle with olive oil and top with more cheese and spring/green onions. Serve!