Combine chicken, buttermilk, and pickle juice in a gallon sized ziplock bag. Chill for 6-24 hours. Drain off and discard marinade. Let chicken sit at room temperature for about 20 minutes before cooking.
For dressing, blend all of the ingredients in a food processor or blender until smooth. Chill until ready to serve.
To roast the corn, heat a skillet over medium high heat. Add the butter and corn, cook and stir for 6-7 minutes, or until corn starts to brown. Set aside.
For chicken: Combine the powdered sugar, onion powder, garlic powder, paprika, salts, and pepper in a small bowl. Sprinkle over the chicken breast.
Cook over medium high heat with the olive oil until internal temperature reaches 165 degrees, about 4-5 minutes per side. Let sit 5 minutes before cutting into cubes or slices.
While the chicken is cooking, chop the lettuce, sliced the eggs, and grate the cheese. Half tomatoes if desired.
To assemble salad, divide the lettuce and spinach between 4 plates. Top each with chicken, roasted corn, shredded cheese, bacon bits, sliced boiled egg, and tomatoes.
Either serve dressing on the side, or drizzle it over each salad.