Sausage meat, browned in its own fat, is used here in lieu of the usual plain ground pork. The shrimps are added to the meat to allow them to soak up the flavors of the rendered fat. If you can get Thai sausages, the better. Otherwise, use the best spicy and garlicky sausage meat that you can find.Peanuts make a lovely addition to this salad but is listed here as an optional ingredient. That's for the benefit of people with allergy.