Heat olive oil in a paella pan or wide skillet over medium heat.
Add the sliced chorizo and cook until the fat renders and the edges become slightly crisp.
Stir in the onion and bell pepper, sautéing until softened and translucent.
Add the garlic, smoked paprika, and saffron threads, stirring for 30 seconds until fragrant.
Pour in the tomato puree and cook for 2 minutes to concentrate the flavors into a thick base.
Stir in the rice to coat it with the oil and spices, then pour in the seafood stock.
Season with sea salt and black pepper, bring to a simmer, then reduce heat to low.
Cook undisturbed for 10 minutes, then nestle the shrimp, cod, and mussels into the rice.
Scatter the peas on top, cover, and cook for another 8-10 minutes until the seafood is cooked and liquid is absorbed.
Garnish with fresh parsley and serve with a lemon wedge to brighten the flavors.