Preheat oven to 475 degrees F.
Remove liver and tie squab with kitchen twine.
In a copper roasting pan, sear squab in vegetable oil over high heat. Add garlic and transfer to oven and continue roasting until meat is pink.
Cut stem of swiss chard into 3-inch triangles. Bring pot of water to boil. Add celery root and cook until tender. Remove from heat and puree. In another pot, add 1/2 cup creme fraiche and cook until reduced by 25 percent. Add celery root puree. Season with salt, pepper and nutmeg.
In a separate pot of boiling, salted water, add swiss chard triangles and cook until tender. Set aside and keep warm.
In saute pan, add 1 tablespoon butter, onions and mushrooms, saute for 3 minutes. Add remaining 1/2 cup creme fraiche and swiss chard leaves. Cook until reduced and cooked through, about 5 minutes.
Add liver to roasting squab and leave 1 minute.
Remove all from oven, separate legs and breast from carcass, reserve liver. Chop carcass using a French knife and return to stove with bones, garlic and wine. Reduce to 1/3, add stock and simmer 5 minutes longer. Add 1 tablespoon butter and press through in a china cap.
Put dish together by placing puree of celery root in middle of a large plate. Display sliced breast and legs around the puree. Using a round cookie cutter, mound swiss chard leaves and liver in a tower on top of the puree. Place sauce around plate and finish by placing triangles of chard on sauce evenly spaced around the plate.
This recipe was provided by professional chefs and has been scaled down from a bulk recipe provided by a restaurant. The FN chefs have not tested this recipe, in the proportions indicated, and therefore, we cannot make any representation as to the results.;
Recipe courtesy of Cuistot, Palm Springs, CA