01 - In a small bowl, whisk together 2 tbsp olive oil, 1 tbsp lemon juice, 1 tsp honey, 1/2 tsp salt, and 1/4 tsp black pepper. Place chicken breasts in a shallow dish or resealable bag, pour over marinade, and let sit for at least 15 minutes while you prepare other ingredients.
02 - Preheat grill or grill pan to medium-high heat.
03 - Brush nectarine halves lightly with olive oil.
04 - Grill chicken breasts for 5-7 minutes per side, or until cooked through and juices run clear. Remove from grill and let rest 5 minutes before slicing.
05 - Simultaneously, grill nectarine halves for 2-3 minutes per side until grill marks appear and nectarines are slightly softened. Remove and slice each half into wedges.
06 - In a large bowl, massage chopped kale with a pinch of salt until slightly softened, about 1-2 minutes.
07 - In a small bowl, whisk together 3 tbsp olive oil, 2 tbsp fresh lemon juice, 1 tsp Dijon mustard, 1 tsp honey, 1/2 tsp salt, and 1/4 tsp black pepper until emulsified.
08 - Add sliced red onion, grilled nectarines, basil, and feta to the kale. Drizzle with vinaigrette and toss to coat evenly.
09 - Slice the grilled chicken and arrange on top of the salad. Sprinkle with toasted pecans or walnuts if using. Serve immediately.