1. Preheat oven to 350 degrees. Line a 9-inch pie plate with one of the pie crusts.
2. Add celery, 1 cup onions and red bell pepper to a frying pan. Add butter and cook on medium-high heat until vegetables are soft.
3. Add heavy whipping cream, 3⁄4 cup onions and minced garlic to the pan and stir. While stirring, add cream of mushroom soup, egg, parsley flakes and wine.
4. Sprinkle bread crumbs over ingredients.
5. Add in crawfish tails and simmer for about 5 minutes.
6. Pour crawfish mixture into bowl. Stir in cayenne and white pepper.
7. Pour into pie crust and cover with second pie crust. Trim excess dough if needed.
8. Cut slits into pie. Next, mix a touch of milk or a touch of water with 1 whipped egg and brush it all over the top of the pie.
9. Bake pie for 30-45 minutes or until the crust is a golden brown.
10. Let cool for 15 minutes and serve.