Sort through the beans to be sure there are no pebbles or other random oddities and put into a soup pot. Cover the beans with water and soak overnight. In a pinch, you can do the boil-and-one-hour-soak that is described on every bag of beans, but I always find they split too early. That could, of course, be user error. Draining and rinsing before coking are imperative to get rid of the prospect of too many ... bubbles. Moving on.
Drain and rinse the beans well in a colander. Let them drain as you go to next step.
Chop the garlic and onion ... doesn't have to be too finely ... and saute in the olive oil over medium heat. You are looking for translucency and a heavenly aroma. Do not brown the aromatics. This will take a minute or two at most.
Place the beans into the pot with the onions and garlic and add water to two inches above the beans. This is not a point to get anxious about... just make sure the beans are covered with room to grow. And grow they will. Add the tomatoes and salt and give it all a stir. OPTIONAL but a great treat: if you have any leftover rinds or bits thereof of Parmigiano-Reggiano (never throw them away; they stay forever in the freezer in a sealed container/bag), plop a piece or two into the pot now. Your frugality in saving rinds will be rewarded.Bring to a boil, then reduce heat and simmer until the beans are tender, about 1 hour 20 minutes. This can be longer or shorter depending on the beans. Starting at about the 45 minute mark, start tasting one for texture - should be creamy but not mushy; if they've started splitting, they are definitely done). When the beans are done, turn off the burner and let the pot sit covered off the heat. Bring another large pot of salted water to a boil. Cook the pasta for only half the time called for on the box.
Drain the pasta and add it to the beans, reserving about 2 cups of the cooking water. Add a generous amount of ground pepper to the beans and pasta - I use about 1 TBS. Turn the heat under the bean/pasta pot to medium-low, and maintain a very slow simmer until the pasta is al dente, adding enough reserved pasta water to keep it slightly brothy or to your taste. Stir occasionally to keep pasta from sticking. Lid on if you want to retain brothiness (what I do) or off if you want it thicker right off the bat.
Ladle into bowls, garnish with a a bit of the chopped parsley and a sprinkling of the shredded cheese.
Yield: Enough to feed at least 8 hungry folks, maybe more if you add a salad and bread.