This won first prize in The 2009 Old Farmer’s Almanac Recipe Contest! That year, contestants had to enter recipes using buttermilk.
Heat the butter in a medium saucepan over medium-high heat. Add the onion and cook for 5 to 7 minutes, or until tender. Stir in the flour and cook for 1 minute. Gradually whisk in the broth and bring to a boil, whisking constantly. Reduce the heat to medium-low, add the corn, and simmer for 5 minutes. Add the shrimp, stir, and cook until the shrimp turn pink, about 2 minutes. Stir in the buttermilk and the seafood seasoning. Remove from the heat, cover, and let stand for 4 minutes. Stir in the parsley and serve.