Rinse and drain the beans. Cover them with water in a large pot or Dutch oven, season heavily with salt, then stir in the oregano, bay leaves, and ¼ cup (60ml) of the olive oil. Bring the pot to a boil, then lower the heat and simmer until very tender, 1.5 - 2 hours.
While the beans cook, prep the marinated vegetables. In a small bowl, combine the sliced bell pepper, shallot, capers, chopped parsley, and red wine vinegar. Season with salt and pepper, then drizzle in 2 tablespoons of the olive oil. Set aside.
Once the beans are tender, heat another 2 tablespoons of olive oil in a separate pot or Dutch oven over medium heat. Sauté the garlic in the oil until fragrant and starting to color, then stir in the red wine. Simmer 5-10 minutes, until the wine has reduced by half. Use a slotted spoon to transfer the beans to the pot with the reduced wine, then add in two cups of the bean broth. Next, stir in the olives, prunes, and the remaining ¼ cup (60 ml) of olive oil. Bring to a simmer and cook, uncovered, until the flavors blend together and the sauce starts to thicken.
Season the beans again with salt and black pepper, as needed. Serve in bowls with a garnish of the marinated peppers, a drizzle of olive oil, and a slice of hearty sourdough or country bread!