In a large frying pan over medium flame add oil and allow to get hot.
Add 1/4 the amount of tortilla triangles and fry on either side till hard, crisp and golden.
Remove from pan on a paper towel lined bowl to drain. Repeat with remaining tortilla triangles till all are fried.
Set to the side.
If there is still a puddle of oil in the pan discard it. In the same pan add chopped onion and saute over a medium flame for a minute or two.
Add crisp tortilla triangles back to the pan and mix in the onion.
Next pour enchilada sauce over the top and mix well. Let them cook for a 3 minutes to dry out the sauce a little.
Top with enchilado and jack cheese. Mix to incorporate and allow to melt in.
Remove from pan and top with queso fresco, crema, cilantro, and avocado.