Cooking prawns isn't easy. While the word "prawn" can refer to either small, lobster-like shellfish or any large shrimp, "Cook's Illustrated Magazine" reports that true prawn and jumbo shrimp are similar enough to be interchangeable in recipes. However, knowing what you're working with doesn't solve the problem of overcooking. Both true prawns and jumbo shrimp contain lean, quick-cooking meat that dries out easily. With a little knowledge about the best ways to cook prawns, you can keep that from happening.
"Poaching" means cooking foods in barely simmering liquid. This method is good for prawns because the low temperature of the liquid cooks the prawns slowly, helping to prevent overcooking. The July 2007 issue of "Cook's Illustrated Magazine" recommends using barely simmering water spiked with fresh herbs, lemon juice, and minced shallots. Prawns are done when they turn pink and are just firm to the touch. Dunk the prawns in ice water if using in a cold dish like shrimp salad, or serve immediately.
Steaming is another gentle cooking method particularly suited to prawns. If you've got some time, you can make oven packs using prawns, aromatic herbs like fresh parsley, and aromatics such as sliced onion. Seal in aluminum foil and cook at 300 for five to 10 minutes. For a faster meal, place prawns, a citrus marinade, and dried onions in a microwave steamer bag -- or a microwave safe bowl -- and cook on high until the prawns are pink and have curled up.
Cooking prawns in oil adds a richness to the lean meat, but requires more attention than steaming or poaching. If you don't want to use much oil, use a heavy-bottomed, nonstick pan and add 1 to 2 tbsp.of olive oil. Heat the oil over medium-low heat until shimmering, then add the prawns. The website Fine Cooking recommends pulling the prawns when they are just firm, as they will continue to cook after you remove them from the heat. To remove excess oil, drain them on paper towels.
Frying isn't something you want to do all the time -- that much fat isn't good for you -- but it can be the perfect method for cooking prawns for a special occasion. Using a batter such as a tempura batter protects the prawns from the intense heat of the oil. For your safety, use a fry thermometer to keep tabs on the oil's temperature, being careful not to let the oil get too hot. To prevent splatters, pat the prawns dry with paper towels before you fry them.