To cook the farro, bring a large pot of water to boil. Add the farro and boil until al dente, about 30 minutes. Drain and rinse with cool water.
While the farro cooks, prepare the dressing. In a small bowl, whisk together the olive oil, lemon juice, minced garlic, dijon mustard, salt and pepper.
In a large bowl combine the cooled farro, parsley, cucumber, tomatoes, and red onion. Pour on the prepared dressing. Toss gently to combine all of the ingredients. Serve immediately or chill for an hour to allow the flavors to develop.
Notes
Farro is a high protein, whole wheat grain. You can find it in the grain section of most grocery stores. Barley, quinoa, or bulgur can be substituted.
You can use precooked farro or par-cooked farro, you will just need about 4 cups total of the cooked grain for this salad.
If you like to add mint to your tabbouleh salad, you can add about half a cup of chopped mint along with the parsley.
Store in an airtight container in the refrigerator for up to five days.