I have always had a theory that great stuffing is just like making a great potato or pasta salad. Using different breads for stuffing adds flavor, mixing rye with Italian or a nice pumpernickel or other flavorful breads makes it better! Adding extra not usually used veggies makes a big difference in the taste, too. I have always had great results mixing bread types, fresh or day old on sale instead of dried bread crumbs. The magic in the taste is the use of different bread. This was a smaller version of stuffing that will suit 2 or 4 people.
Slice your half loaf of day old bread, doesn't have to be all the same size slices, and tear the slices apart into chunks in a large mixing bowl.
Slice your black olives into the bowl, add the chopped onion and celery, add the liquid from the from the black olives and liquid with the sliced mushrooms stems and pieces to the bowl.
Grind some black peppercorns over the bowl, and add the minced garlic. Stir this mixture until all the bread is moist, you may need to add a little water to get all the bread moist.
Add the rinsed black beans, stir well. Transfer to a covered casserole baking dish. Bake covered at 375 degrees for a half hour, or if baking with other food at a higher temp, keep an eye on the dish until the liquids in the stuffing are bubbly. Remove lid to brown the top of the dressing if you prefer it crisped on top, and bake another 10-15 minutes. Serve.
As with any stuffing, you can make this up the day before, and bake it next day. Just make sure the container you have the stuffing in is tightly sealed so it doesn't dry out.