Heat the oven to 450ºF. Wrap the beets in foil and place on the middle rack. Roast for 1 hour and 15 minutes, or until soft and fragrant. Remove from oven and let cool. Gently rub away the peels. Cut into a small dice and refrigerate until chilled. (This step can be done several days in advance.)

Combine the farro and 3/4 cup water in a saucepan. Bring to a boil; reduce heat and cover. Cook for 15 minutes, or until the farro and soft and the water is absorbed. Let cool.

Peel the lemon and remove the seeds. Add the lemon, shallot and olive oil to a blender. Blend on high until smooth. Thin with 1 tablespoon water.

In a large bowl, combine the cooled beets and cooked farro. Toss with the dressing, blue cheese crumbles, and pistachios.