For almost a century, freed slaves and their descendants lived isolated on the barrier islands of the American Lowcountry, situated along the coasts of South Carolina and Georgia. A favorite meal consisted of native foods boiled in a large kettle and served community style, similar to Northeastern clam bakes. Cooking a Lowcountry boil is a simple, one-pot technique that produces a bounty of flavor. Try different ingredients each time you make a boil to keep your boils interesting.
Cut corn ears into two or three pieces, depending on whether the ears are long or short. Quarter onions, preferably Vidalia sweet onions local to the Lowcountry. Halve new potatoes or quarter medium potatoes and cut the sausage into 2-inch or 3-inch portions.
Devein the shrimp. Cut a slit in the shell along the back of the shrimp from top to bottom. Do not remove the shell or break off the tail. Make a slit in the back of the shrimp from top to bottom and remove the black vein.
Fill the pot with enough water to more than cover all of your ingredients and turn on the heat. Just before the water boils, stir in half the boil seasoning mix. Add the potatoes and let boil for approximately 10 minutes. Reduce the heat to a steady, rolling boil and add the corn and sausage. Season to taste. Boil for approximately five minutes, then add the onions and crab legs or crabs. Cook for approximately 10 to 15 minutes, or until the crab turns red. Turn off the heat and add the shrimp. Boil until the shrimp turns bright pink or orange, no more than three to five minutes.
Drain the water as soon as the shrimp changes color. The shrimp will continue to cook in the shell, and overcooking shrimp makes it grainy and tough. Pour the contents of the pot onto a long table covered with newspaper or aluminum foil.
Serve with or without utensils, depending on how authentic you want to be.