Place chicken broth in a large stock pot (I use a 7 quart cast iron dutch oven) over medium high heat. Add potatoes, carrots, and corn.
In a large skillet also over medium high heat, Thaw crawfish and frozen peppers and onions. Once thawed, turn off heat and set skillet to the side. There will also be a lot of liquid in the skillet, save this as well!
After carrots and potatoes have been cooked until tender, add the crawfish and peppers and onions with the liquid from the skillet to the stock pot. Stir well.
Add the Turnip greens, Parsley and Old Bay seasoning and bring to a gentle boil. Turn heat to low and simmer for 15 minutes, stirring occasionally.
Pour in cream and potato flakes. Stir well. Simmer five to ten minutes more. Serve hot with a hearty bread. Leftovers are even better the next day!