Gulf Prawns with Spicy Tamarind Sauce

This is one of our staples. The recipe is in Andrea Nguyen's Into the Vietnamese Kitchen: Treasured Foodways, Modern Flavors. I process tamarind pulp into liquid then freeze it in ice cube trays. Two cubes equal 1/4 cup. This was Tess' idea after I told her that Gulf Coast Prawns were on sale at Nugget, our local grocery store.