Using an electric mixer, beat the egg whites until foamy. Gradually add the sugar, beating until a loose meringue forms. Beat in the Old Bay Seasoning, chili powder, Worcestershire sauce, cayenne, and salt. Mix in the nuts and butter, then mix in the Parmesan.
Divide the nuts between 2 parchment-lined rimmed baking sheets, spreading them in a single layer. Bake, switching the baking sheets halfway through, until golden brown, 30 to 40 minutes
Let cool and store in an airtight container at room temperature for up to 1 week.