In a large skillet or pan, heat the olive oil over medium heat. Add the Italian sausage and cook until browned, breaking it up with a spoon, about 5-7 minutes.

Add the diced onion and cook until softened, about 3-4 minutes. Stir in the minced garlic and cook for an additional 1 minute until fragrant.

Add the red bell pepper, zucchini, and cherry tomatoes to the pan. Cook for about 5 minutes, stirring occasionally, until the vegetables are tender.

Stir in the dried oregano, dried basil, red pepper flakes (if using), and season with salt and pepper.

Add the orzo pasta and chicken broth to the pan. Bring to a boil, then reduce the heat to low. Cover and simmer for about 10-12 minutes, or until the orzo is cooked and has absorbed most of the liquid. Stir occasionally to prevent sticking.

Once the orzo is cooked, remove the pan from heat and stir in the grated Parmesan cheese. Adjust seasoning if necessary.

Garnish with fresh basil leaves before serving.