Rinse the dried beans and place them in a large bowl. Cover with water and let soak overnight.
Drain and rinse the beans before cooking.
In a large pot, bring 4 cups of water or vegetable broth to a boil. Add the soaked beans and bay leaves.
Reduce the heat to low, cover, and simmer for about 1-1.5 hours, or until the beans are tender. Check occasionally and add more water if necessary. Drain the beans and discard the bay leaves.
In a large skillet, heat the vegetable oil over medium heat.
Add the chopped onion and cook until softened and translucent, about 5 minutes.
Stir in the minced garlic and chopped bell pepper, and cook for another 2 minutes.
Add the diced tomatoes, tomato paste, ground coriander, ground cumin, paprika, dried thyme, and cayenne pepper (if using). Cook for about 5 minutes, stirring occasionally, until the tomatoes break down and the mixture thickens.
Add the cooked beans to the skillet with the tomato mixture. Stir well to combine.
Add salt and black pepper to taste.
Reduce the heat to low, cover, and let the Lobio simmer for 20-30 minutes to allow the flavors to meld.
Garnish with chopped fresh cilantro.
Enjoy your meal!