In a pot on medium heat, allow the farro and 5 cups water to simmer for 25- 30 minutes until the farro is softened but still slightly chewy. Drain in a colander and rinse with cold water to cool.
In a small bowl whisk together the crushed garlic, mustard, olive oil, and vinegar. Season with salt and pepper.
In a serving bowl, combine the pistachios, farro, shredded kale, chopped parsley, and celery. Toss with the dressing and serve.