1/4 - 1/2cupbean juice (more or less as desired)(57 to 115, liquid left in the pot after beans are cooked)
The dried beans have to be soaked for at least 8 hours, so the night before soak beans in a large bowl of water, (then after the 8 hours drain and rinse).
In a medium pot add the drained beans and cover with an inch (2 1/2 cm) of water. Cover and cook on medium/high heat until boiling, once boiling half uncover and continue to cook until tender, approximately 50 minutes (might need to go longer so taste a bean after 40 minutes and then again after 10 minutes, until cooked to desired tenderness). With a slotted spoon remove cooked beans from the pot leaving the bean juice.
In a medium bowl, add chopped onion, celery, and flaked tuna, toss gently to combine, then add cooked beans, salt, oil and bean juice, again toss gently to combine. Serve immediately or at room temperature. Buon Appetito!
Canned beans can also be used, skip the first part and toss beans with ingredients.