Step 1

Cook the spaghetti in a large pot of heavily salted water until al dente.

Step 2

At the same time you start cooking the pasta, add the olive oil, sliced garlic, and diced red onion to a large pan. Turn the heat to low. Let cook for about ten minutes while the pasta cooks. Stir occasionally, being very careful not to let the garlic burn. You want the garlic and onion to be soft and fragrant, but not dark brown or burned.

Step 3

Once the spaghetti is al dente, reserve about 1 cup of pasta water (you likely won't use all of this but you want to have more on hand just in case). Then drain the pasta.Add the cooked pasta to the pan with the olive oil, garlic, and red onion. Add the chopped parsley, red pepper flakes, and 1/4 cup pasta water. Mix. Add the parmesan and mix and toss well in the pan. Add more reserved pasta water if needed.

Step 4

Serve with more parsley and parmesan on top if desired. Enjoy!