Warm butter in a pan over medium-high heat, tilting the pan so the butter coats the bottom. Add prawn to the pan. Cook prawn until they are bright pink on the outside and the meat is opaque, 4 to 5 minutes.
Mix prawn, tomatoes, lemon juice and garlic in a 25cm baking pan.
Bake in the preheated oven until tomatoes release their juices, about 45 minutes. Stir in breadcrumbs and parsley. Sprinkle Parmesan cheese evenly over the top of the prawns.
Continue baking until juices have been soaked up and the Parmesan cheese has started to melt, about 15 minutes.