In a large skillet, heat the olive oil over medium-high heat. Add the Italian sausage and cook, breaking it up with a spoon, until browned. Remove the sausage from the skillet and set aside, leaving the drippings in the pan.
Add the sliced bell peppers and onion to the skillet. Cook, stirring occasionally, until softened, about 8-10 minutes.
Add the minced garlic, dried oregano, and red pepper flakes to the skillet. Cook for another minute until fragrant.
Return the cooked sausage to the skillet. Stir to combine with the vegetables. Season with salt and black pepper to taste.
Cook for an additional 5-10 minutes, or until the sausage is heated through and the vegetables are tender.
Serve hot, with your favorite sides such as rice, pasta, or crusty bread.
Notes
This dish is versatile and can be served in many ways. Consider serving in hoagie rolls for a delicious sandwich.