Begin by bringing a large pot of salted water to a boil. Once boiling, add the fresh tortelloni and cook according to package instructions, typically around 3-5 minutes, until they are tender but still al dente. Drain and set aside, reserving a cup of the pasta cooking water.
In a large skillet, melt the salted butter over medium heat. Add the finely chopped onion or shallots, cooking for about 3-4 minutes until they become translucent. Next, add the chopped sundried tomatoes and minced garlic, stirring for an additional 1-2 minutes until fragrant.
Pour in the two tins of chopped peeled tomatoes and bring the mixture to a gentle simmer. Let it cook for about 5-7 minutes, allowing the flavors to meld together. You can use a spoon to break down the tomatoes slightly if you prefer a smoother sauce.
Once the tomato sauce has simmered, reduce the heat to low and stir in the fresh cream. Mix well until the sauce is creamy and well-combined. If the sauce is too thick, you can add a bit of the reserved pasta water to reach your desired consistency.
With the sauce now creamy and luscious, fold in the roughly chopped baby spinach and basil leaves. Stir until the spinach wilts and is incorporated into the sauce, about 2-3 minutes.
Gently toss the cooked tortelloni into the sauce, ensuring each piece is coated in the creamy mixture. Serve hot, topped with freshly grated Parmesan cheese for that extra layer of flavor.
