Place first 4 ingredients in 13x9-inch baking dish, toss to coat. (I used a disposable roasting pan) squeeze juice from lemons over shrimp mixture, and stir. Add lemon halves to pan. Sprinkle evenly with parsley; and dot with butter.
Bake at 375° for 25 minutes, stirring after 15 minutes. Serve in pan. You can serve with french bread and sop up the sauce in the pan.really good!