In a bowl, mix together the ingredients for the tzatziki, season to taste with sea salt & pepper. Set in the fridge to chill while you prepare the rest of the meal.
Prep the grill. Fire up the grill to get the grates hot.
Prep the shrimp. In a bowl, add the shrimp, lightly spray it with oil, then add the remaining seasonings. Thoroughly rub the seasoning on the shrimp, then add to a wooden or metal skewer.
Slice a lemon or onion in half and cover one side with (avocado) oil, then rub the grates to help ensure the food does not stick. Place the lettuce on the grates on one side and the shrimp skewers on the other side. Grill for 6 – 8 minutes, or until sear and char marks appear, then flip the shrimp and place the lettuce on its other side to grill.
Note: COOKING TIMES WILL VARY depending on the closeness the grill is to the flames or coals, the weather outside (hot vs cold), and/or if you’re using an open flame. Most important point is to monitor the food to ensure shrimp is cooked through AND lettuce is seared (anywhere from 2 minutes per side to 8 minutes per side)
Add the lettuce to a bowl, top with tzatziki, garnish and then enjoy with shrimp!