To cook the farro: In a medium saucepan, combine the rinsed farro with at least three cups water (enough water to cover the farro by a couple of inches). Bring the water to a boil, then reduce heat to a gentle simmer, and cook until the farro is tender to the bite but still pleasantly chewy. (Pearled farro will take around 15 minutes, unprocessed farro will take 25 to 40 minutes.) Drain off the excess water and mix in the lime juice, garlic and salt. Set aside to cool.
Preheat grill or grill pan over medium heat. Brush the grill with oil to prevent sticking. While farro is cooling, grill sliced peaches and planks of halloumi. Keep a close eye as halloumi will only take 30 seconds to 1 minute per side - you don't want it melting entirely and leaving a sticky mess in your barbecue. Peaches will take 1-2 minutes per side, just to give them grill marks and bring out their natural sweetness.
To assemble salad, combine 1 ½ cups of cooled farro, one full package of baby arugula, corn, red onion, pumpkin seeds, grilled peaches and halloumi. Drizzle with 1⁄3 cup of Cilantro Lime Dressing (recipe follows) and toss to combine. Add more dressing to taste. Serve!
Place all ingredients in the food processor, except the olive oil and salt. Turn the food processor on, and slowly drizzle in the olive oil until incorporated into the dressing. Season to taste with salt before serving.