Prepare farro according to package directions.

In the meantime, heat oil in a pan and add the mushrooms, celery, and a pinch of salt and pepper. 

Sauté until the mushrooms are soft, about 10 minutes. 

Add the garlic, chestnuts, and nutmeg, and sauté an additional three minutes. Taste for salt and adjust accordingly.

Once farro is cooked, combine with the vegetable mixture. Garnish with parsley and serve.