preheat grill to 375-400.
place one piece of tilapia on a large sheet of tin foil. lightly season each side with garlic & herb seasoning. Repeat with other piece.
heat butter in microwave or stovetop. add red pepper flakes and juice of 1 lemon. Stir.
pour sauce on top of each piece of tilapia. top with 2-3 lemon slices depending on size of fish.
make a tent with the foil around the salmon and seal all edges (see photo). place on grill, shut cover and "bake" for 14 minutes.
open foil pack and carefully transfer tilapia to a plate. Top with parsley. Serve with rice, Cauliflower rice (click here for recipe) or Cauliflower Hash (click here for recipe) or quinoa salad (click here for recipe).