In a large skillet, heat the olive oil over medium heat until shimmering.
Carefully remove the casing from the Italian sausage and crumble it directly into the skillet. Cook the sausage, stirring frequently with a spatula, until it is nicely browned and cooked through, about 5 to 7 minutes.
Once the sausage is browned, add the sliced onion and red bell pepper to the skillet, followed by the minced garlic. Sauté the mixture for an additional 3 to 4 minutes, or until the vegetables are tender and fragrant.
Next, gently fold in the broccoli florets, stirring everything together. Pour in about ¼ cup of water to introduce some steam for the broccoli. Immediately cover the skillet with a lid and let it cook for 5 to 6 minutes, or until the broccoli turns bright green and is tender yet crisp.
After 5 to 6 minutes, uncover the skillet. Season the mixture with red pepper flakes, salt, and freshly cracked pepper to taste. Evenly sprinkle the grated Parmesan cheese across the top and stir gently until combined.
Allow the dish to cook for an additional 2 minutes, stirring occasionally, until the cheese has melted and the entire dish is heated through.
Remove the skillet from the heat and garnish your delicious creation with fresh chopped parsley right before serving.
Notes
Serve hot in shallow bowls with extra Parmesan and black pepper for added flair.