Heat the olive oil in a paella pan or wide skillet over medium heat and sauté the sliced chorizo until it begins to brown and release its oils.
Add the diced onion and red bell pepper to the pan, cooking until the vegetables are softened and the onion is translucent.
Stir in the minced garlic, smoked paprika, sea salt, and black pepper, followed by the tomato puree, cooking for 2 minutes to create a concentrated flavor base.
Add the Bomba rice to the pan and stir for 1 minute to ensure each grain is well-coated in the oil and spices.
Pour in the seafood stock and add the saffron threads; bring the mixture to a boil, then reduce the heat to a steady simmer.
Allow the rice to cook undisturbed for about 10-12 minutes so the liquid is mostly absorbed.
Gently press the shrimp and scrubbed mussels into the rice, then cover the pan and cook for another 5-8 minutes until the shrimp are opaque and the mussels have opened.
Increase the heat to medium-high for the final 60 seconds to develop the 'socarrat' crust on the bottom of the rice.
Remove from heat, garnish with freshly chopped parsley, and serve immediately with a lemon wedge.