Heat olive oil in a large deep skillet or pot over medium heat.
Add the crumbled sausage and cook, stirring occasionally, until browned and cooked through, about 5-7 minutes.
Add the chopped onion and cook until softened, about 3 minutes.
Stir in the minced garlic and cook for 1 minute until fragrant.
Pour in the canned diced tomatoes with their juices and the chicken broth.
Add the penne pasta, dried oregano, dried basil, crushed red pepper flakes, salt, and black pepper.
Stir well to combine and bring the mixture to a boil.
Reduce heat to medium-low, cover, and simmer for 12-15 minutes, stirring occasionally, until the pasta is tender and most of the liquid is absorbed.
Remove from heat and stir in the grated Parmesan cheese until melted and combined.
Taste and adjust seasoning with additional salt and pepper if needed.
Serve immediately, garnished with chopped fresh parsley.