1. In a large skillet over medium heat, cook bacon for about 3 minutes. Add onion and cook for an additional 3-5 minutes or until bacon is browned, stirring occasionally. Add garlic, cook 30 seconds. While bacon is cooking, cook pasta as directed on the package. Once pasta is done, drain and set aside.
2. Once the bacon has been cooked, set aside in a small bowl, reserving one tablespoon of bacon fat in the skillet, discarding the remaining fat.
3. Stir the heavy cream into the skillet containing bacon fat and bring to a boil. Reduce heat to low and simmer for 3 minutes. Keep warm.
4. Add diced bacon, cooked pasta, parmesan cheese, pepper and parsley, as well as any other optional additions at this time to cream mixture. Toss well to coat pasta and serve.