Bring a large pot of salted water to a boil over high heat. Add the penne and cook according to package instructions, about 10 minutes.
Meanwhile, heat the olive oil in a large skillet over medium heat. Add the onion and garlic and cook, stirring frequently, until fragrant, about 3 minutes.
Add the mushrooms and bell pepper and cook until the vegetables are tender, about 5 minutes.
Add the vegetable broth to the skillet and simmer for 10 minutes.
Stir in the heavy cream, Parmesan cheese, and parsley. Simmer for an additional 5 minutes.
Drain the cooked penne and add it to the sauce. Toss to combine.
Serve the pasta with additional Parmesan cheese and parsley, if desired.
Interesting Facts
This dish is a great way to use up vegetables that are in season in the springtime.
Adding a bit of cream to the sauce helps to thicken it and give it a luxurious texture.
For a vegan version of this dish, use a vegan cream substitute instead of the heavy cream.