Make the Tortilla:

1. Preheat the oven to 350 degrees F.  Grease a 10 x 12 rimmed baking sheet (or use two 8 x 8 square pans).  Place all the tortilla ingredients into a high speed blender and blend on high for 1-2 minutes.  If mixture is too thick, add a little water (mixture should be thick yet still be able to be poured).  Pour mixture onto the rimmed baking sheet and bake for 20-25 minutes or until fully cooked.  Don't worry about overcooking the tortilla as it will absorb some of the moisture from the taco meat.  Remove the tortilla from the oven and slice into sections to make 2 layers that will cover an 8 x 8 baking dish.

Make the Filling

1. Place ground meat in a large skillet and cook on medium heat until starting to brown.  Once meat begins to brown, add onion and continue to cook until onion begins to soften.  Add all additional ingredients (except cheese) and cook until water has evaporated (10-20 minutes)

Assemble the Casserole

1. Take 1/3rd of the taco filling and layer it on the bottom of the dish.  Layer with tortilla sheet.  Repeat layers until no more tortilla remains.  Sprinkle with cheese (if desired).  
2. Place casserole in the oven for 10-15 minutes or until fully heated.
3. Once cooked, divide the dish by 8 and enjoy.