Bring 1 ½ cups of water to a boil in a small saucepan. Remove from heat, add the dried mushrooms, and let stand 15 to 30 minutes. Drain the mushrooms, reserving the liquid, then squeeze the mushrooms to extract as much liquid as possible. Chop the dried mushrooms into small pieces and set aside.(If you get the sense that the mushrooms had grit in them, you can pass the liquid through a very fine-mesh strainer, and swish the mushrooms after they've been soaked in a few changes of water until they're free of dirt, before chopping.)

Heat the olive oil in a soup pot or medium-sized Dutch oven, over moderate heat. Add the diced bacon and cook a few minutes, stirring, until it's cooked through. Add the onions, garlic and rosemary, and cook 2 to 3 more minutes, until the onions are soft and wilted.

Add the mushrooms and season lightly with salt and freshly ground black pepper. (The bacon and stock have salt, so you can add more later, if needed.) Cook the mushrooms until they're soft and cooked through. Stir in the farro and cook for another minute or two, stirring frequently. Add the wine and continue to cook until the wine is almost completely absorbed.

Pour in the chicken stock, the mushroom liquid and stir in the chopped dried mushrooms. Increase the heat until the liquid begins to boil, then reduce the heat to a low simmer and cover. Cook until the farro grains are tender and almost all the liquid is absorbed, about 50 minutes to 1 hour, stirring every so often.

Turn off the heat and stir in the Parmesan and parsley. Taste, and season with additional salt and pepper, if desired.