In a Dutch oven, over medium heat, cook chorizo in olive oil until some of the fat is rendered and it begins to brown, about 5 minutes; add in the bell pepper and cook until it begins to soften, 3 minutes.
Add in onion and cook 5 minutes; add in garlic and cook until fragrant, about 1 minute.
Add in the beans, water, and bay leaf; bring to a simmer, stirring occasionally, cover tightly and place in oven for one hour.
Season with salt, stir, replace cover and cook in oven until beans are tender, 45 minutes to 1 hour longer.
The consistency should be like a thin stew (if not add more water, 1/4 cup at a time); discard bay leaf and season to taste with additional salt, if necessary, and pepper.
Meanwhile, in a large skillet, with a tight-fitting lid, heat the olive oil over medium heat; add in garlic and parsley and cook until fragrant 1 or 2 minutes.
Add in white wine and reduce to a thin syrup, about 3 minutes; stir in crushed tomatoes and let cook until slightly reduced, 5 minutes.
Add in the shrimp and clams, cover tightly, increase heat to high and cook, shaking pan frequently, until clams have opened, about 5 minutes.
Gently stir clams into beans and heat through; season to taste with more salt, if needed.
Ladle stew into shallow soup or pasta bowls and sprinkle each with about 2 teaspoons of peperoncini and parsley.