Heat butter over low heat to melt. Once melted, add garlic and onion to sautÃ© till clear.
Add Shrimp and Worcestershire sauce, cook until shrimp are pink. Salt and pepper to taste.
Toss Shrimp, butter mixture and linguini together and place in a casserole dish.
Cover top of mixture with parmesan cheese.
Bake in a 350 degree oven until cheese is melted.
Sprinkle with parsley and serve.