Cut away the green stalks of the leeks. Cut leeks lengthwise into four sections and then cut into coarse slices. These will cook down.
Heat pan and add a tablespoon of olive oil. Sauté mushrooms until cooked down by about a third. Add more oil if needed during this sauté time. There will be a lot of liquid, please leave in the pan. Remove two cups of cooked mushrooms and set aside. Leave the rest in the pan and add the leeks
Add the marjoram, rosemary and thyme and cook another 15 minutes on medium heat. Set aside
In a heavy pot, melt butter over medium/high heat. Add the flour, smoked paprika, pepper and saffron. If you're adding salt, do so sparingly. Stir constantly to avoid burning. (note, the roux will be dark because of the paprika) Add milk and stir to incorporate into the roux. Add all of the beef broth. Add the mushroom/leek mixture and all of the juices in the pan. Bring to a simmer and let cook another 10-15 minutes
In a small pan, fry the pancetta about 5 minutes. Drain and set aside.
With an immersion blender, blend the contents of the broth until smooth, Add the sour cream and blend again
Add 1 cup of cold, cooked farro
Add the pancetta and the reserved two cups of mushrooms
I used leftover farro from another dish I cooked earlier in the week.To cook farro, use two cups of water for every one cup of farro. Add a pinch of salt. Bring water to a boil, stir and reduce heat to low. Simmer with a lid for 40 minutes or so or until tender.