As far in advance as you can, sprinkle both sides of the chicken with the salt and pepper. Ideally you'll let it sit for 30 minutes so the salt can penetrate the meat, but if you're short on time, you can move ahead right away.
Wash the salad greens and dry in a salad spinner.
Heat a grill or grill pan until hot.
Drizzle 2 teaspoons of olive oil onto the chicken and rub all over both sides.
Place the chicken skin-side down on the grill until it has good grill marks, and then flip and grill until the chicken is cooked through (registered 160 degrees F on a thermometer). Transfer the chicken to a cutting board and let it rest for 10 minutes.
Whisk the olive oil, honey, whole grain mustard, lemon juice and hot mustard together in a bowl.
Slice the chicken into bite-sized pieces.
Drizzle a few spoonfuls of dressing onto the greens and toss to coat. Salt and pepper to taste.
Arrange the chicken on top of the salad and drizzle with the remaining dressing.