To cook the farro, follow package directions. Quick cook farro will usually have you add the farro to a pot with the broth or water, bring broth or water to a boil over high heat and reduce the temperature to low. Cover and simmer for 10 minutes. Remove from heat and allow to sit for 5 minutes. Drain any excess liquid and set aside.
Preheat oven to 400 degrees. Toss the carrots with the olive oil, chili powder, cinnamon, and salt. Spread the carrots evenly on a baking sheet (you can line with foil or parchment paper). Cook until they are browned and slightly soft - about 25-30 minutes depending on their size. Be sure to toss them every 10 minutes or so. Once finished, allow to cool for 5 minutes.
While the carrots cook, whisk together all the ingredients for the dressing. Prepare salad with arugula, cooked farro, cheese (if using), toasted seeds, and dried cranberries (or pomegranate seeds). Toss with carrots and dressing.
I find this makes more dressing than I need so I like to save it for future salads. This recipe can be made ahead, just wait to toss the dressing with everything until you're ready to serve. There's nothing worse than a soggy salad!