In a large skillet, melt the butter over medium heat. Add the scallion and bell pepper and cook, stirring, until the vegetables have softened, about 5 minutes. Add the crawfish and cook, stirring, until warmed through, about 3 minutes. Stir in the Creole seasoning and cook for 2 minutes longer.
Arrange the chips on a platter and spoon the crawfish and any juices over the top. Drizzle the queso over the chips, sprinkle with parsley and serve.