I just do salt and pepper and then throw the in a frying pan with clarified butter, about 2-3 minutes on each side (a little more or less depending on the size). I always cook them thawed. They are so simple but delicious and easy to throw on a salad or with a side of veggies and sweet potato. Shrimp this way (or salmon cooked the same way) are staples of mine on nights when there is no time to make a more involved meal!
Garlic and ghee! Plus some salt and pepper. I always thaw first, they can overcook if you try to cook from frozen. Easiest way to thaw them fast is throw them in a colander under cold running water, then dry them on a paper towel when they're thawed. It only takes a few minutes.