- Olive oil
- 1/2 yellow onion, thinly sliced
- 1 tablespoon red pepper flakes, more to taste
- 1/2 pound penne pasta
- 1/2 (14-ounce) can crushed whole tomatoes
- 1.5 ounces Parmigiano Reggiano, grated
- Zest of 1 lemon
- Parsley, to garnish
- Bring a medium-sized pot of salted water to a boil.
- In a saute pan on high heat, add 2 tablespoons of olive oil and the sliced onion. Stir and add a pinch of salt. Once onions begin to turn brown, add a ladleful of water from the pasta pot.
- Continue to cook down the onions and add water until they are soft and medium brown in color, about 25 minutes.
- Once onions are caramelized, add a pinch of red pepper flakes and the tomatoes to the saute pan, lower the heat to medium and simmer. If the sauce looks too thick, add water from the pasta pot to thin out.
- Add pasta to the boiling water, and cook 2 minutes less than box instructions.
- Once the pasta is cooked, add it to the sauce. Turn the heat to high, add a ladle of pasta water and stir well for 2 minutes. Remove from heat, add the cheese, another ladleful of water, and stir to combine. Stir in lemon zest and more water if needed to thin out.
- Transfer to a plate and garnish with more cheese, parsley and a splash of olive oil.