After removing from the heat, and the eggs in a trickle, with constant stirring. Start mashing the beans, while you add the onions sauteed with the celery and milk with the eggs. After blending, fill up 2/3 of a baking tray with the mixture.
Then grate the cheese and fill it to the brim with the mashed mixture and top it with grated cheese. Bake in a preheated oven until browned.