1. Put the dried mushrooms in a small bowl and pour the hot water over them. Set aside for 20 to 30 minutes.
2. In a medium saucepan, heat 1 quart (1l) of water until boiling. Add the farro or wheat berries and cook until they’re slighty tender, but still a ways from being fully cooked, about 10 to 15 minutes. Turn off the heat and, using an immersion blender, pulse the wheat berries six or so times so that some of them (roughly one-quarter to one-third of them) are broken up and cracked. Strain though a mesh stainer. (I reserved the liquid, just in case I needed it later if I didn’t have enough stock. I didn’t use it, but you may want to hang onto it, just in case.)
3. In a small bowl, mix the minced shallots and garlic. In a medium skillet, heat some olive oil and cook the bacon, stirring, until cooked through but not crisp. Transfer to a paper towel-lined plate to drain and cool. Drain off excess fat, wipe the pan clean, and add the radicchio. Cook the radicchio over medium heat, stirring constantly with a little of the shallot and garlic mixture, and a pinch of salt, until wilted. You may need to add a little olive oil if the radicchio sticks. Transfer the radicchio to a plate.
4. Squeeze the mushrooms dry and coarsely chop them. Put them on the plate with the radicchio.
5. Heat the stock in a saucepan and keep it warm on the stove.
6. In a 4- to 6-quart (4-6l) casserole or Dutch oven, heat some olive oil with the butter, sprigs of thyme, along with the remaining shallots and garlic. Cook over medium heat, stirring frequently, until the shallots and garlic are soft and fragrant, about 2 to 3 minutes.
7. Add the drained farro or wheat berries and stir to combine with the shallots and garlic. Add the white wine and continue to cook, stirring, until the wine is absorbed. Using a ladle, add enough of the warm stock to cover the farro so there is a layer of liquid about 1/4-inch (1cm) floating on top. Adjust the heat so that the mixture is simmering. It should be bubbling gently, not boiling.
8. Continue to cook, adding additional stock (about 1/2 cup/60ml at a time) as the layer of liquid on the top gets absorbed, while stirring. When two-thirds of the stock has been used, add the mushroom liquid and continue to cook, adding more stock and stirring. The process will take 20 to 30 minutes.You may not have used all the stock. If you need a bit more liquid, use the reserved cooking liquid.
9. When the farro has softened add the bacon, radicchio, chopped dried mushrooms, and minced thyme. Cook a few more minutes, plucking out the thyme branches and adding the grated Parmesan. Stir while the mixture simmers, until everything is absorbed and incorporated.