I grew up on these---as part of the #6 dinner---and have yet to find another hole in the wall that fixes them this way.
Here is the chile relleno as prepared by Gay & Larry's of Rubidoux, California.
1 27 oz. can ortega whole green chiles (12-14 per can)
3 c. Krusteaz Complete Buttermilk Pancake mix
2 cups water
12-14 1/2" by 2 1/4" strips velveeta cheese
1/2 cup cornstarch
Drain chiles, lay on paper towel, pat dry. Mix pancake mix with water--it will be thick. Place cheese inside chile, dredge in cornstarch and dip in batter covering whole chile. Deep fry about two minutes at 375.