In a large pot, bring salted water to a boil. Add the 12 ounces of spaghetti and cook according to package instructions until al dente. Drain and set aside, reserving about a cup of pasta water.
In a large skillet, heat 1 tablespoon of olive oil over medium-high heat. Season the 1 pound of chicken breasts with salt, pepper, and Italian seasoning. Add the chicken to the skillet and cook for about 5-7 minutes, or until golden brown and cooked through. Remove the chicken from the skillet and set aside.
In the same skillet, add the remaining 1 tablespoon of olive oil. Add the 1 cup of minced onion and sauté for 3-4 minutes until translucent. Stir in the 2 teaspoons of minced garlic and sauté for an additional minute until fragrant.
If using, add the 2 teaspoons of anchovy paste to the skillet, mixing well. Then, add the 1 cup of capers, 1 cup of Kalamata olives, and the 2 cups of marinara sauce. Stir to combine and let it simmer for about 5 minutes.
Add the sautéed chicken back to the skillet, along with the drained spaghetti. Toss everything together, adding reserved pasta water a little at a time until you reach your desired sauce consistency. Stir in the 1 cup of chopped fresh basil just before serving.
Plate your Pasta Puttanesca with Chicken, garnishing with extra basil if desired. Dig in and savor each bite of this flavorful dish!
