01 - Preheat oven to 400°F. Line a rimmed baking sheet with parchment paper.
02 - Toss the pitted and halved cherries with 1 teaspoon olive oil. Spread in a single layer on the prepared baking sheet and roast for 12 to 15 minutes until softened and slightly caramelized. Remove from the oven and set aside to cool.
03 - Combine the rinsed farro, 2 cups water, and 1/2 teaspoon salt in a medium saucepan. Bring to a rolling boil, then reduce the heat to low and simmer uncovered for 20 to 25 minutes until the farro is tender yet retains a pleasant chew. Drain any remaining liquid and let the grains cool slightly.
04 - In a small bowl or Mason jar, whisk together the extra-virgin olive oil, fresh orange juice, vinegar, honey, Dijon mustard, salt, and pepper until the dressing is fully emulsified and creamy.
05 - In a large mixing bowl, combine the cooked farro, roasted cherries, orange segments, arugula, red onion slices, orange zest, and toasted nuts. Drizzle with the citrus vinaigrette and toss gently until every component is evenly coated.
06 - Transfer the salad to a serving platter or divide among individual bowls. Scatter the crumbled feta over the top. Serve immediately, or refrigerate for up to 2 hours to allow the flavors to develop further.