1. Rinse the anchovies in water and then cut them into small pieces.
2. Saute the garlic and olive oil on low heat, careful not to burn, around 2-3 minutes.
3. Add the anchovies into the oil and continue to saute on low for 2-3 minutes.
4. Add 1-2 tablespoons of pasta water to the oil and continue to saute until the sauce comes together.
5. If you want, add red pepper flakes and/or capers.
6. Add the drained pasta to the sauce and the butter and cook for several minutes, stirring as you do.
7. When the pasta is cooked through, turn off the heat and add the parsley on top (with traditional Italian food you do not add parmesan, or any cheese, too pasta with seafood).