Hi. I'm a black bean fanatic, and I've found the "Black Bean Sauce" that's available at the grocery stores to be inadequate.
What you need to do is go to your local Asian grocery and ask for "Chinese black beans" or "fermented black beans." You can also purchase this online: http://www.mingspantry.com/m-ferbb.html
As for recipes, try this:
GREEN BEANS IN BLACK BEAN SAUCE
1 lb fresh green beans, trimmed
4 garlic cloves
2 jalapenos or other hot chiles
2 T fermented black soybeans
3 T rice vinegar
2 T tamari (or soy sauce)
1.5 t potato starch (or cornstarch)
1 T brown sugar
2 T sake or other rice wine
Cut the green beans into equal lengths of about 1.5 inches. Blanch the green beans for 3 minutes. Set aside.
Mince the garlic. De-seed the jalapenos and finely dice. Lightly mash black beans and chop. Mix together the garlic, jalapeno, and black beans. Set aside.
Mix together the rice vinegar, tamari, starch, sugar, and sake. Set aside.
Fill a glass with water and set handy next to the stove. Put a wok or skillet over high heat. When the pan is hot, dump the garlic mixture into the pan. Stir fry for one minute, adding water as the mixture begins to stick -- add just a little at time. Add the green beans and stir fry for 5 minutes, again adding water just as needed. Add the vinegar mixture, mixing until evenly coated and sauce thickens. Serve immediately.