Prepare your favorite pie crust and refrigerate.
Preheat the oven along with cast iron skillet to 350 degrees.
In a mixing bowl, whisk the eggs and milk together, adding a little salt and pepper as desired.
Prepare add-in ingredient but chopping up or heating up as necessary.
Remove pie crust from the fridge and roll out. Gently place in the preheated cast iron skillet.
Spoon add-in ingredient into the pie crust and spread evenly.
Pour the egg and milk mixture on top of that.
Finally, sprinkle cheese on the very top.
Bake for about 30 minutes, or until the crust and cheese are lightly browned and the eggs are set.
Serve hot!