How to make
Soak the beans for 12 hours, boil until tender and set the water aside. Slice the onions, fry them in oil until golden and sprinkle with salt and black pepper.
In a pre-greased with oil fireproof container, alternate between layers of beans and fried onions. Top with a little oil and add some of the water in which you had boiled the beans.
Bake for about 25 minutes in a moderate oven.