In a large sauté pan, warm 3 tablespoons olive oil over low heat. Add 3 crushed garlic cloves and 5 anchovy fillets.
Let them gently bubble, stirring occasionally, for 5–6 minutes, until the garlic softens and the anchovies fully melt into the oil. Keep the heat low to avoid browning the garlic.
Increase the heat to medium and stir in 1/4 teaspoon crushed red pepper flakes. Add 2 tablespoons tomato paste and cook, stirring often, for 2–3 minutes until the paste darkens slightly and smells rich.
Pour in 1/2 cup dry white wine, scraping up any bits from the pan. Simmer for 2 minutes.
Stir in 1 can (28 ounces) of hand-crushed San Marzano tomatoes with their juices. Season with 1/2 teaspoon kosher salt and freshly ground black pepper. Bring to a gentle simmer.
Lower heat to medium-low and simmer uncovered for 15–20 minutes, stirring occasionally, until slightly thickened. Remove the garlic cloves. Stir in 1/4 cup parsley and the zest of 1 lemon. Taste and adjust seasoning.