Boil pork sausage for 15 minutes, then slice.
Preheat oven to 450 degrees F.
Prepare dough as instructed on box. Spread into a pizza dish and paint with a thin coat of melted butter.
Season crawfish. Spread a thin layer of pizza sauce over pizza. Add crawfish, onions, sausage and jalapeņo peppers. Cover with a layer of mozzarella cheese. Bake for 15 minutes.
NOTE: Shrimp may be substituted for crawfish, but do not use sausage if you use shrimp.