Preheat oven to 350 degrees. Place shrimp in baking dish.
Melt butter in a small saucepan over low heat. Add garlic and saute 30 seconds. Alternately melt butter with garlic in a small microwave safe dish in microwave. Stir lemon into butter mixture.
Pour butter mixture over shrimp in baking dish, season with salt and pepper and red pepper flakes, toss shrimp then spread into an even layer.
Bake in preheated oven until shrimp are cooked through (pink and opaque) about 9 - 13 minutes. Sprinkle with parsley and serve warm, spooning sauce over shrimp.