Peel the onions and cook in boiling water for 8 minutes. Drain and cut in half. Put half all onions in a greased baking pan, sprinkle with minced parsley mixed with breadcrumbs.
Slice the eggplants in order to obtain discs of about one centimeter thick. Arrange in a greased baking pan. Cut the tomatoes into thin slices and place a slice on top of each eggplant. Cut the mozzarella into thin slices and place a slice on top of each tomato, one for eggplant.
Rinse the beans and put them in a pressure cooker. Fill the pressure cooker with water up to the internal mark. Add a handful of salt, garlic, sage, black peppercorns and some bay leaves. Close the cover of pressure cooker, put on the stove and raise the flame until the whistle.