In a large deep sauté pan, heat oil over medium flame. Add chorizo, cook for 1 minute or until it begins to brown and render bright red fat. Add onion, stir, cook another 1–2 minutes. Once the onions turn translucent, add in garlic, stir, let the mixture continue cooking over medium heat until garlic becomes fragrant but has no color, about another 1 minute.
Add crushed tomatoes, salt and pepper. Cover and allow to cook for 10 minutes over low-medium flame. While tomato sauce is cooking, drain and rinse beans. Remove cover and add beans, parsley and lemon zest; stir to combine. Place cod fillets into the sauce; they should be half submerged in the sauce. Cover with lid and simmer for 6–7 minutes.
Serve family-style or in deep bowls. Garnish with lemon zest and fresh parsley. Serve with crusty bread and a side salad.