Follow these instructions carefully for a delicious and perfectly cooked seafood dish.

1. Prepare the Seafood:
* Shrimp: Ensure they are peeled and deveined. Pat them thoroughly dry with paper towels. Season lightly with salt and pepper.
* Scallops: If using large sea scallops, remove the small, tough side-muscle if it’s still attached. Pat them very dry with paper towels – this is crucial for getting a good sear. Season lightly with salt and pepper.
* Mussels: Scrub the mussels under cold running water to remove any grit. Pull off any “beards” (fibrous threads) that may be attached. Discard any mussels that are open and don’t close when you tap them, or any with cracked shells.
* Fish (if using): Cut into 1-inch pieces and pat dry. Season lightly with salt and pepper.

2. Start the Spicy Tomato Sauce:
* In a large, heavy-bottomed pot, Dutch oven, or deep skillet with a lid, heat the 3 tablespoons of olive oil over medium heat.
* Add the chopped onion (or shallots) and cook, stirring occasionally, until softened and translucent, about 5-7 minutes.
* Add the minced garlic and red pepper flakes (and fresh chili, if using). Cook for another 1-2 minutes until fragrant, stirring constantly to prevent the garlic from burning. Be careful, as red pepper flakes can burn quickly.

3. Build the Sauce Flavor:
* If using, pour in the 1/2 cup of dry white wine. Increase the heat slightly and bring to a simmer, scraping up any browned bits from the bottom of the pot with a wooden spoon (this is deglazing and adds flavor). Let the wine reduce by about half, about 2-3 minutes.
* Stir in the 28-ounce can of crushed tomatoes, 1/2 cup of seafood or chicken broth, and 1 teaspoon of dried oregano. Season with a pinch of salt and freshly ground black pepper.
* Bring the sauce to a gentle simmer. Reduce the heat to low, cover, and let it cook for at least 10-15 minutes to allow the flavors to meld. Taste and adjust seasoning if needed (you might need more salt depending on your broth and tomatoes).

4. Cook the Seafood:
* If searing scallops separately (optional but recommended for best texture): While the sauce simmers, heat 1 tablespoon of olive oil or butter in a separate non-stick skillet over medium-high heat until shimmering. Add the dry, seasoned scallops in a single layer, ensuring not to overcrowd the pan (cook in batches if necessary). Sear for 1-2 minutes per side until golden brown and just cooked through. Remove from skillet and set aside.
* Add Mussels: Add the prepared mussels to the simmering tomato sauce. Stir gently, cover the pot, and cook for about 3-5 minutes, or until most of the mussels have opened. Discard any mussels that remain closed after cooking.
* Add Fish (if using): If you’re using firm white fish, gently nestle the pieces into the sauce around the mussels. Cover and cook for another 2-3 minutes, or until the fish is opaque and flakes easily.
* Add Shrimp and Scallops (if not seared separately): Add the prepared shrimp and scallops (if you didn’t sear them earlier) to the pot. Stir gently to submerge them in the sauce. Cover and cook for another 2-4 minutes, or until the shrimp are pink and opaque, and the scallops are cooked through. Do not overcook the seafood, as it will become tough and rubbery.

5. Finish the Dish:
* Once all the seafood is cooked, remove the pot from the heat.
* If using, gently stir in the 2 tablespoons of butter until melted. This adds a lovely richness and gloss to the sauce.
* Stir in the 1/2 cup of chopped fresh parsley.
* Taste the sauce one last time and adjust salt, pepper, or red pepper flakes if needed. A small squeeze of fresh lemon juice directly into the pot can also brighten the flavors.

6. Serve Immediately:
* Ladle the Spicy Seafood Medley into large, shallow bowls.
* Garnish with extra fresh parsley and serve with lemon wedges on the side for squeezing over.
* Crucially, serve with plenty of crusty bread (like a baguette or ciabatta) for soaking up every last bit of that delicious, spicy sauce.