Cook the Pasta: Bring a large pot of salted water to a boil. Add the pasta and cook according to package instructions until al dente. Drain and set aside

Prepare the Seafood: While the pasta is cooking, heat half the olive oil in a large skillet over medium-high heat. Add the shrimp and calamari, sautéing for 1-2 minutes until just turning opaque. Remove and set aside.

Sauté the Aromatics: In the same skillet, add the remaining olive oil, garlic, and chili pepper (if using). Sauté for 1 minute until fragrant.

Add Wine and Tomatoes: Pour in the white wine, scraping any browned bits off the bottom of the pan. Add the diced tomatoes and tomato paste. Season with oregano, salt, and pepper. Simmer for 5 minutes.

Cook the Shellfish: Add the clams and mussels to the skillet, cover, and cook for 5-7 minutes until the shells open. Discard any that do not open.

Combine: Return the shrimp and calamari to the skillet. Add the cooked pasta, tossing everything together gently, ensuring the pasta is coated in the sauce and the seafood is evenly distributed.

Serve: Garnish with fresh parsley before serving. Enjoy the rich flavors of the sea in this hearty dish.