Wash beans and soak overnight according to package directions.
Drain beans and place in a large pot or Dutch oven; add ham hocks, 6 cups water, and cook over medium-high heat until it comes to a boil.
Reduce heat to medium low, cover, and cook until beans are tender, about 2 hours.
While the beans are cooking, prepare the guiso in a large skillet; heat vegetable oil, over medium heat, add tomatoes, onion, green onions, salt, garlic, cilantro, and ground cumin and cook 10 to 15 minutes.
Add the guiso when beans are almost tender; also add plantains, carrots, and salt.
Cook another hour.
DIRECTIONS USING SLOW COOKER - Use the same ingredients, except only 4 cups water instead of 6. Wash beans and soak overnight, according to package directions. Drain and place beans in a slow cooker with 4 cups water and ham hocks. Cook on high 2 hours. Prepare the guiso as above and add that, plantains, carrots, and salt to slow cooker. Cover and cook for an additional 3 hours.
DIRECTIONS USING PRESSURE COOKER - Use same ingredients, except 4 cups water instead of 6. Wash beans and soak overnight according to package directions. Drain and place beans, 4 cups water, and ham hocks in a pressure cooker. Cook on medium heat for 35 minutes. Meanwhile, prepare the guiso as above. Release pressure from pressure cooker. Add guison, plantains, carrots, and salt. Cook over medium heat an additional 20 to 30 minutes. Test for doneness. Cook an additional 10 minutes, only if needed.