Chop the onion and halve the garlic.

Warm the pan up on the stove over medium heat. Pour the oil into a large pan or skillet, let it warm up for a minute. Sauté the onion and garlic for 2 to 3 minutes until fragrant. Then, add in red pepper flakes and cook for another 1-2 minutes.

Add in the can of crushed tomatoes and sugar. I also like to fill the can with a little water about ¼ cup (60mL).

Let the sauce cook for 40 minutes over low heat. Stir occasionally and do not let it become too bubbly. It will look a bit dried out, that is okay.

Bring a large pot of salted water to a boil. Boil until al dente. Reserve about 1 ½ cups of pasta water, and drain the rest.

Add the pasta to the pan. Gradually, add in the reserved pasta water until the sauce coats the pasta and it becomes glossy. You may not need all of the pasta water. It will just depend on how saucy you want the pasta to be. Taste the pasta and add salt to your preference.

Garnish with fresh parsley and more red pepper flakes if desired.