Brown pork in skillet over medium-high heat until cooked through, about 8 minutes. Drain excess fat. Set aside.
Heat the olive oil in a medium saucepan on medium-high heat.
When the oil is hot, add the onions and garlic. Cook until the onions start to get soft (but before they get brown), about five minutes.
Add the tomatoes, tomato paste, salt, pepper, and Italian seasoning. Mash up the whole tomatoes into smaller chunks.
Keep heating sauce until it starts to bubble (a.k.a. simmer), then turn the heat to low, and simmer uncovered. After 20 minutes, add the reserved cooked pork, then simmer for an additional 5 minutes.
For the fettuccine: A good time to start boiling the water is just before you add the tomatoes to the sauce. Fill a large pot with water. Bring to a boil, and cook for the time directed on the pasta box.
When the fettuccine is cooked, drain it and put it in a large bowl. Add the sauce. Serve!