Season with pepper, and salt if needed (the anchovies will be salty). Serve the pasta in warmed bowls, with Parmesan, and the garlic ciabatta, if serving.
To serve, put the spaghetti in a large warm serving bowl and top with the remaining Parmesan and a twist of black pepper. Serve the warm garlic bread alongside.
Meanwhile, strain beans, discarding cooking liquid, garlic and thyme. Add beans and pasta to broth and simmer until flavors meld, about 3 minutes. Turn off heat, stir in ½ cup grated Parmesan and ...