Preheat oven to 325°F. Place frozen pie shells on two large baking sheets. Let defrost for 15 minutes.
First, in a heavy 12-inch skillet, melt 2 Tbsp. of butter and 2 Tbsp. olive oil and cook down the (chopped seasoning mix) onions, celery, bell pepper, and garlic over a medium-high fire until the onions soften and turn transparent. Continuously stir the mixture as it cooks so that the garlic doesn't burn and turn bitter. Remove from pan and add this to a blender or food processor and mix until no chunks remain.
On medium heat add the remaining butter and 2 Tbsp. olive oil and two packets of crawfish to the pan. Stir and simmer for 5 minutes.
Use fork to pierce the bottom of the pie shells. Pre-bake the pie shells for 8 minutes. Next, pour in the mushroom soup, minced seasoning and the Worcestershire Sauce, taking care to fully combine all. Once the mixture is smooth, stir in the herb and garlic seasoning, salt, black pepper, and cayenne pepper. When softly boiling, it's time to stir in the cornstarch and water mixture to thicken. Remember that as it cooks, the mixture will begin to thicken (actually, you should plan to cook the base over a medium heat for about 5 minutes).
When the base reaches the consistency of a thickened roux, this is when you add and fold in the Velveeta cheese and cream cheese, green onions, dill and parsley. Again, taste for the right amount of seasoning and spice, cover the pan, and cook once more for about five minutes, this time on a low fire so that you don't "toughen" the crawfish tails. Add bread crumbs to thicken if needed. Add the parmesan cheese.
Then when the pie crust has pre-baked and is ready, fill it with heaping spoonfuls of the crawfish stuffing, Sprinkle bread crumbs and parmesan cheese on top of filled pie shells.
Slide the filled pie shells back into the oven, and bake it for another 20 minutes or until the crust turns a flaky golden brown. To be authentic, serve the crawfish pie "table warm" alongside an ice cold green salad with a French vinaigrette dressing and a frosty glass of Barq's Root Beer. C'est si bon!