Bring about four quarts of water to a boil in a large stockpot. Season generously with salt. It should taste like the ocean. When the water comes to a boil, add pasta and cook for about 7 minutes, until it’s softened but still very toothy.
While the pasta boils, heat a few tablespoons of olive oil in a large skillet, and add garlic, anchovies, and capers. Cook, stirring frequently, until the garlic just begins to soften. If the garlic begins to brown, turn down the heat and keep warm until the pasta is ready,
Add the cooked pasta to the skillet, along with about ⅓ cup of pasta water from the stock pot. Bring to a simmer and cook until the pasta is perfectly al dente. Season with salt and pepper and add the French butter to finish. Toss with the parsley and serve.