Bring a pot of salted water to a boil and cook the spaghetti according to the package instructions until al dente. Drain and set aside.
In a large pan, heat the olive oil over medium heat. Add the minced garlic and sauté for about 1 minute, until fragrant.
Add the chopped anchovy fillets to the pan, stirring them into the garlic and oil until dissolved.
Stir in the crushed tomatoes, sliced black olives, capers, and red pepper flakes. Simmer for 10 minutes, allowing the flavors to meld.
Season the sauce with salt and black pepper to taste.
Add the cooked spaghetti to the sauce and toss until well coated.
Serve hot, garnished with fresh chopped parsley or shredded cheese.