In a Dutch oven, cook the chorizo in oil, over medium heat, until the chorizo has rendered some fat and begins to brown, about 5 minutes; add bell pepper and cook until it starts to soften, 3 minutes more.
Add the onion and cook until it softens, 5 minutes; add garlic and cook until fragrant, 3 minutes.
Stir in the dried beans, water, and bay leaf; bring to a simmer, stirring occasionally.
Cover tightly and bake in oven for one hour; add salt, stir, and continue cooking, covered, until beans are tender, 45 minutes to 1 hour.
The consistency should be like a thin stew, if not, stir in a little water; remove bay leaf and discard.
Season to taste with more salt and pepper.
NOTE: The dish can be prepared to this point a day ahead of time and refrigerated.
In a large skillet (that has a tight fitting lid) heat oil over medium heat and cook garlic and parsley 3 minutes; add white wine and reduce to a thin syrup, about 3 minutes.
Add crushed tomatoes and cook until slightly reduced, 5 minutes.
Add in shrimp and clams, cover tightly, and raise heat to high; cook, shaking pan often, until clams open, about 5 minutes.
Stir clams and shrimp into warm beans and heat through; taste and adjust seasoning.
Ladle stew into shallow soup bowls and garnish each with 2 teaspoons chopped pepperoncini and parsley, if desired.