In a large pot, bring salted water to a boil and cook the orecchiette according to package instructions until al dente.
Meanwhile, in a large skillet, cook the sausage over medium heat, breaking it up with a wooden spoon, until browned and cooked through. Remove the sausage from the skillet and set aside.
In the same skillet, sauté the onion and garlic until translucent.
Add the chopped broccoli to the skillet and sauté for 5 minutes, until tender.
Add the diced tomatoes to the skillet and let the sauce simmer for 10 minutes.
Add the cooked sausage to the skillet and season the sauce with red pepper flakes, salt, and pepper to taste.
Drain the cooked orecchiette and add it to the skillet with the sauce and sausage.
Toss the pasta with the sauce to combine.
Serve the orecchiette with broccoli and sausage hot, topped with grated Parmesan cheese.