To prepare the rice heat 2 tbs of oil over medium heat in a saucepan, add 2 tbs of onion and garlic, and cook until soft, about 3-5 minutes.
Add the rice, stir until well coated with the oil. Add the seafood broth, bring to a boil over high until the broth is gone, reduce heat to low, cover and let simmer for about 15 minutes or until the rice is tender but firm, save for later.
Heat the remaining 3 tbs of oil on medium heat in a large sauté pan, add the chopped onions and crushed garlic, stir frequently and cook until the onions are tender, about 5 minutes.
Add the cumin, achiote powder, salt, pepper, ½ of the chopped cilantro, and diced bell pepper. Cook for another 5 minutes, stirring frequently.
Add the raw seafood, start by adding the seafood that needs more time to cook first (large shrimp, clams, mussels), followed by the ones that require less cooking time (smaller shrimp, calamari, scallops), stir and cook for about 3 minutes.
Stir in the cooked rice, mix well and cook until the seafood is done, about 5 minutes.
Add the remaining ½ of the chopped cilantro, and additional salt or pepper if needed.
Serve with patacones or thick green plantain chips, onion curtido or salad, avocado, lime slices, and aji criollo hot sauce.