Add the lemon juice, olive oil, honey, garlic, thyme, salt, pepper, and red pepper flakes (if using) to a large measuring cup and whisk until everything is combined and the honey has dissolved. Set it aside.
Use some paper towels to pat dry the chicken then place it in a large glass dish or Ziploc bag. Pour the marinade evenly over the tenders and refrigerate them for 2 ½ hours or overnight.
When ready, remove the chicken from the marinade and set it aside. Strain the remaining marinade through a fine-mesh strainer (discard any accumulated bits) and save to baste the chicken.
Heat the gas grill to medium-high, grease the grates, then add the chicken. Baste it with the remaining marinade while it cooks.
When the chicken starts to turn white along the edges, flip and continue to baste and grill. Remove it from the heat when the internal temperature reaches at least 165 degrees F, after about 8 minutes of cook time.
Notes
Whisk the marinade until the honey dissolves. If any pockets of it remain, it ends up burning the chicken!
Don’t overcook the chicken. Use an instant-read thermometer and pull the chicken off the grill as soon as the temperature reaches 165 degrees F. Smaller tenderloins will cook faster than larger ones.
Let the tenders rest for at least 5 minutes before slicing into them.
Keep the grill lid open to prevent overcooking. They cook so fast that closing the grill will overcook them.
Store leftovers in an airtight container in the refrigerator for up to 4 days or in the freezer for up to 2 months.
Reheat them in a covered skillet over low heat with a splash of chicken broth, in the oven at 350 degrees F for 10 minutes, or in the air fryer at 350 degrees F for 4-5 minutes.
This nutrition information is based on the exact products I used in this recipe. Brands and sizes of products could alter exact nutrition and should always be calculated independently.