3.5 to 4 lbs skinless, boneless chicken breasts or thighs (or a mix)
½ c Kosher salt
2 T sugar
Fresh ground pepper
1/3 c Dijon mustard
1/3 c mayonnaise
½ tsp chopped fresh rosemary
Remove the tenderloins from the chicken breasts for more even cooking; reserve for another use.
Combine salt, sugar, and enough water to cover. Brine the chicken for an hour or two.
Heat a gas grill to medium high.
Combine mustard, mayo, and rosemary in a large bowl.
Pat chicken dry, season with pepper. Add chicken to bowl, stir to combine and coat.
Spread the chicken out on the grill.
Cover and grill for 8-10 minutes total, flipping once. (rotate for grill marks if desired.)
With careful attention, the tenderloins can be cooked the same way, just for about half the time. I pan fried them on the stove the next day.