Bring a large pot of water to boil, season with salt and cook pasta until al dente or according to the package directions. Save ½ cup pasta water and drain pasta. Meanwhile, cut the cod into 1-inch chunks and set aside.
Heat the olive oil in a large sauté pan over medium-high. Once hot, add the garlic and when it’s sizzling and very fragrant, about 30 seconds to 1 minute, add the tomatoes. Cook the tomatoes, stirring often, until they become very juicy and sauce-like, about 10 minutes. Turn down the heat to medium-low and stir in the tomato paste, wine, olives, capers, anchovies and chili flakes.
Stir the cod chunks into the tomato sauce and simmer for 5 minutes. Then stir in the pasta to coat each piece. If the sauce seems a little dry, stir in splashes of the reserved pasta water.
When ready to serve, coarsely chop the basil leaves and quickly stir into the sauce. Turn off heat. Transfer pasta entrée to plates and drizzle some olive oil over the top.