This is a combination of two different quiche recipes I've used in my 33 years of marriage, and I've tweaked it into my own semi-homemade creation. My family absolutely loves it, and I hope yours does, too!
Place frozen mirepoix mix into a small microwave-safe bowl, and microwave on high for 1-2 minutes, or until thawed.
In a large bowl, beat together eggs, milk, flour, thyme, salt & pepper.
Add ham, thawed mirepoix, and cheese. Mix well, and pour into pie crust, making sure all ingredients are evenly distributed within the crust.
Place pie pan onto a cookie sheet (I use a 14" round pizza pan), and bake in preheated for 40-50 minutes, or until quiche is firm in the middle. [Based on different ovens I've had over the years, it can take up to 60 minutes to bake.]
Remove quiche from oven and let set for about 15 minutes to cool a little, and let the quiche set.