Soak the beans for 12 hours in water, then boil them with a little olive oil and salt. Shred the broccoli into florets and blanch them for 2-3 minutes in boiling water, then immediately pour ice water over them.
Heat the olive oil and fry the cumin, chopped garlic and leeks. Do not fry too much, then add broccoli and the beans. Season to taste with a little salt and pepper, transfer into a lightly greased tray.
Sprinkle it with grated cheese and put it to bake for 15 minutes in a preheated 392°F (200 °C) oven.