In a large pot, heat olive oil over medium heat and then add the diced onions.

Boil water with generous amount of salt and start cooking pasta once your onions are starting to cook. Be sure to save a cup of pasta water when your noodles are done before draining.

Cook the onions for about 5 minutes till soft and add the garlic and cook an additional minute. Open the tomato cans and as you pour them in the pot, kind of squeeze them between your fingers to open them up and break them up a bit to allow them to cook down better. Sprinkle the salt and basil in and cook for 15-20 minutes, uncovered over low heat, to not have them splatter everywhere.

Tip the pot to the side a little so the tomatoes are more to one side. Using an immersion blender, blend the tomatoes till mostly smooth. If you don’t have an immersion blender you can use a normal blender as well, just be careful the heat doesn’t pop your lid off your blender.

Pour the cream in and stir to combined. Sprinkle the parmesan cheese in and heat till  melted. Add the cooked pasta in and stir to combine. Add up to 1 cup of pasta water to get your desired consistency. The sauce will thicken as it cools. I typically use about ½ cup but if you have leftovers you may want to add a touch more before putting it in the fridge so when you reheat the leftovers it won’t be too thick.