Season the chicken with olive oil, garlic powder, onion powder, sweet paprika, oregano, and salt. Bake, air fry, or sear and finish in the oven at 400 degrees for 37-40 mins or until cooked through.
Finely dice the red onion and place in a bowl of cold water to reduce the pungent flavor.
Prepare the salad ingredients: thinly shred the romaine lettuce, cube the avocado, finely chop the fresh chives, and toast the walnuts.
Finely chop the cooked or rotisserie chicken and add it to the salad bowl with the red onion, romaine, avocado, chives, and walnuts.
Make the dressing by processing the mayo, sour cream, or yogurt, lemon juice, baby spinach, cilantro, dill, garlic, dijon mustard, olive oil, water, salt, and pepper.
Pour the dressing over the salad and toss well. Finely shave the parmesan cheese and serve.
