Peel shrimp and devein as needed

melt butter into a large skillet over medium-high heat

add onion and next 3 ingredients and saute 7 minutes or until the shrimp turns pink

stir in soup and next 4 ingredients until blended

pour into a lightly greased 11 x 7 baking dish

sprinkle evenly with parmesan cheese

bake at 350°F for 15-20 minutes or until the casserole is bubbly and cheese is lightly browned

NOTE; Unbaked casserole may be made one day in advance. Cover & refrigerate. Let stand at room temperature for 30 minutes before baking> To freeze unbaked casserole prepare as directed, omitting parmesan cheese. Cover tightly & freeze. Let stand for 30 minutes before baking. Bake, covered at 350°F for 50 minutes. Uncover, sprinkle with parmesan cheese, and bake for 10 minutes more or until cheese is lightly browned.