Bring a large pot of water to boil. 10 minutes before the sauce finishes simmering, add the pasta and cook to package instructions. Reserve ¾ cup pasta cooking water. Drain.
Start the Sauce:
In a wide pot, heat the neutral oil over medium heat. Add the butter. Once frothy, add the leeks and cook for 5 minutes until just beginning to soften.
Add the tomatoes and turn the heat to medium-high. Once the tomatoes begin to blister and burst, add the garlic and stir, gently breaking up the tomatoes. Season with salt and pepper.
Simmer the Sauce:
Pour in the vegetable stock and bring to a boil. Reduce heat and season with crushed red pepper. Simmer for 25-30 minutes until thickened and reduced. If the sauce has too much liquid, turn the heat to a low boil to continue reducing it to a jammy consistency. Taste and season again to your preferences.
Sauce the Pasta:
Add the pasta cooking water to the pot and stir to incorporate. Add the pasta and cook for 1-2 minutes, tossing gently, until all the pasta is coated with the sauce. Turn off the heat.
To Serve:
Divide the pasta between shallow bowls and garnish with parsley and a drizzle of extra virgin olive oil, if desired. Enjoy!