Slow Cooker Arrabbiata Sauce

Arrabbiata Sauce is a pasta sauce that is flavored with pancetta. Pancetta is an uncured Italian bacon that adds a nice touch to the sauce. It also has crushed red pepper flakes to give it a subtle kick. But what I love most about this sauce is that I can cook it all day in the slow cooker while I am elsewhere. I like to double the batch. I serve half over pasta and the other half goes into the freezer for when I want to make a baked pasta dish.
Serves 8

1 large onion, diced
5 ounces pancetta or bacon, chopped
2 28 ounce cans of san marzano tomatoes, pureed
2 6 oz cans of tomato paste
1 15 oz can tomato sauce
1/2 cup dry white wine
1 tsp dry basil
1/2 tsp crushed red pepper
3 cloves garlic, minced
1/2 tsp dry oregano
1/4 cup fresh minced Italian Parsley
salt and pepper

In a large skillet cook the onion, garlic and pancetta over medium heat. Drain off any fat and place the onion mixture into the bottom of a slow cooker insert. Add the rest of the ingredients and mix to combine. Cover and cook on low for 8-10 hours or high for 4-5 hours. Serve over cooked pasta and top with freshly grated Parmesan Cheese.