Source: David Leite's - The New Portuguese Table - My Family's White Beans and Sausage
1 pound dried navy, small California white or great northern beans, washed and sorted
1/2 pound bacon
1 large onion, chopped
3 cloves garlic, minced
3/4 pound Chourico, Linguica or Dry-Cured Smoked Spanish Chorizo cut into 1/4-inch slices
1/2 teaspoon dried red pepper flakes, or more to taste
1 tablespoon sweet paprika
water ( I used chicken broth)
Freshly ground pepper
3 tablespoons tomato paste (squeeze tube)
Fresh chopped flat leaf parsley
Heat a large pot over medium low heat. Add the bacon and cook, stirring often, until the fat has rendered and the meaty bits are crisp, about 15 minutes. Using a slotted spoon, transfer to paper towels.
Bump up the heat to medium, add the chourico and sear until lightly browned, 7 to 10 minutes. Transfer the chourico to paper towels.
Pour off all but 3 tablespoons of fat from the pot. Or, if the pot is dry , drizzle in some oil. Add the onions and bay leaf and cook, stirring frequently, until deeply golden brown, 20 to 25 minutes, adjust the heat as necessary to prevent the onions from burning.
Add the garlic and paprika and cook for 1 minute more. Drain the beans and dump them into the pot, along with the chourico and red pepper flakes, and 3 1/2 cups of water (I used chicken broth). Bring to a boil, reduce the heat to low, cover and let burble gently. Stiring occasionally, until the beans are tender. Begin checking at 45 minutes, but it may take as long as 1 1/2 hours , depending on your beans' add more water (chicken broth) if needed.
Fish out and toss the bay leaf. Stir in the tomato paste and bacon and simmer for 10 minutes to thicken the cooking liquid. Season with salt and pepper to taste. Let the beans sit uncovered for 10 minutes to absorb and excess liquid.