Heat the oil in a saucepan or skillet. Add the garlic and half of the beans. Mash them into the oil and cook for a few minutes. Add the broth (less if you want a stew; more if you want soup), the other can of beans and dried herbs. Cover and simmer for 20 minutes over very low heat; if melange gets too thick, add some water. Season to taste with salt and pepper and remove from heat. Stir in sage and parsley. Eat as a soup or on pasta, with bread or rice.