To make crawfish stuffed jalapenos, you'll first need to prepare your ingredients. Peel and slice your jalepenos. Place the jales in a large bowl and cover with cling wrap. Cover the bowl with plastic wrap and refrigerate for at least 1 hour. Preheat the oven to 450 degrees F (232 degrees C) and prepare the filling. Heat the melted butter over medium-high heat. Add the garlic and saute until fragrant, about 1 minute. Stir in the flour and cook, whisking constantly, until the mixture thickens, 2 to 3 minutes. Remove the pan from the heat and stir in 1 cup of the water. Simmer, covered, for 5 to 10 minutes, or until thickened, stirring occasionally. Season with salt and pepper to taste. Serve with tortilla chips or sour cream.