Preheat oven to 400°F; divide tortillas into two stacks and wrap each stack in it's own piece of foil. Place in the preheating oven.
While the oven is preheating I shred the cheese, chop the onions, dice the garlic and add about half of that diced garlic to the Enchilada sauce. Lightly spray a casserole dish or cake pan with cooking spray. Then put a light layer of Enchilada sauce to cover the bottom of the dish.
Remove the tortillas from the oven. On one tortilla, spoon a little sauce into the middle. Add desired amount of cheese (if you want them really cheesy, add more, if you don't, add less. And remember you will want some cheese left over to put on top). Sprinkle a pinch of onions on cheese. Roll loosely and place in pan.
Repeat with the rest of the tortillas.
When all the tortillas are rolled and in the pan, spoon sauce over all the enchiladas. I usually don't use all of the sauce because I like mine with a little thicker consistency. If you like them to sort of "swim" in sauce, then go ahead and use the whole can.
Sprinkle the remaining cheese over the top of the enchiladas.
Sprinkle any remaining garlic and onion on top of cheese.
Bake in the oven for 15-20 minutes. Cooking times may vary.