Combine vinegar, soy, fish sauce, Splenda, red pepper flakes and garlic in a bowl. Stir to combine the Splenda and until it's dissolved.
Combine the chicken and place into a gallon bag with vinegar mixture to marinate.
Squeeze in the juice of the lemon and lemon halves as well into the gallon bag. Seal and let sit for 20 minutes at room temperature. Massage the bag every few minutes to make sure everything is combining.
Prepare a grill over medium high heat.
Remove the chicken breasts from the bag and grill 4-6 minutes per side, while turning.
This recipe serves 4 at 0 SmartPoints per serving on the Blue and Purple Plans. It is 5 SmartPoints per serving on the Green Plan. Also, you can combine a dipping sauce by doubling the ingredients in the first step of the directions. Add a bit of the sauce to each cooked breast.
Recipe by Dee Dee Does at https://deedeedoes.com/20-weight-watchers-green-plan-5-smartpoint-under-chicken-recipes/