The oven does most of the work for this mix-and-bake chicken dinner, featuring sweet citrus and licorice-flavored fennel. If you find the white pith of the orange a little bitter, just pull it away before digging in.
Allergen Note: Contains wheat.
Preheat the oven to 475°F. Set out a cast-iron skillet or ovenproof sauté pan.
Quarter the orange. Trim the fennel, remove the tops, and thinly slice the bulb. Reserve a handful of fronds for sprinkling.
In a large bowl, toss the orange and fennel with 2 tablespoons olive oil and ½ teaspoon salt. Arrange evenly in the skillet. Place the chicken thighs in the bowl, drizzle with the lemon relish and 1 tablespoon olive oil, season with a pinch of salt, and turn to coat. Arrange the chicken thighs on top of the vegetables, skin-side up. Transfer the pan to the oven and roast until the the chicken is golden and no longer pink at the center, 45 to 50 minutes.
Transfer the chicken to a plate to rest. Remove and discard orange peel. Add the cooked farro to the skillet, and toss to coat in the pan juices and warm through.
Return the chicken thighs to the skillet, placing them on top of the farro. Sprinkle with the fennel fronds and serve warm, directly out of the pan.