Bring a large pot of water to a boil for the pasta.
Heat EVOO, 4 turns of the pan, over medium heat. Add anchovies and cover pan with splatter screen or lid. Shake until anchovies begin to break up, reduce heat a bit, then uncover and stir until anchovies melt into oil. Add chilies and garlic, stir a couple of minutes more. Douse with a bit of vermouth and reduce heat to low.
When water is boiling, salt water and cook pasta to al dente. Reserve a cup of starchy water before draining the pasta and add to garlic and oil sauce along with the parsley. Drain pasta and toss to combine. Turn an additional minute in the sauce for the pasta to absorb the flavors.
Puttanesca:
To turn this sauce into a Puttanesca, add 2 pints cherry tomatoes to the Aglio e Olio sauce, cover and cook over medium-high heat to burst tomatoes, 7-8 minutes. Gently mash them up with a wooden spoon and stir in a handful of pitted oil-cured black olives and a few tablespoons of chopped capers. Add the parsley and toss with starchy cooking water and penne pasta.
White Clam Sauce:
For a white clam sauce, add 2 tablespoons chopped thyme and 2 pounds of manila clams to Aglio e Olio sauce. Cover to open clams, add 3 tablespoons butter and the juice of 1 lemon. Stir in parsley and starchy cooking water and toss with linguine.