The key to this dish is the poblano pepper, which is mild compared to some varieties (although your eyes won't think so if you touch the seeds and then try to remove your contacts). It's not only my favorite pepper, it is probably Mexico's most popular pepper.
When shopping for poblanos, you should look for peppers about 6 inches long and 2 1/2 inches wide.
The trick to prepping the peppers for this dish is in the roasting and seeding. I think the best way to roast them is to char them under a broiler or on a gas grill. Turn them over every couple of minutes when the skin closest to the flame has turned completely black.
After the peppers are about 80 percent blackened (which should take roughly 10 minutes), remove them from the oven and seal them in a plastic bag. Allow the peppers to sweat and steam for about 15 minutes.
Remove the peppers from the bag and pull the charred skin off. You will be tempted to do this under running water, but unless you want to be shunned by Mexican chefs everywhere, don't do it, because you will lose a lot of the great pepper flavor.
The next step is to slice from just under the stem to about halfway down the peppers with a sharp paring knife. Use the knife to scrape and remove the seeds, taking care not to tear the flesh of the pepper (or yourself, for that matter).
When stuffing the peppers with cheese or any other filling, make sure not to pack in too much and that the edges of the peppers will still meet.
I'm sharing a traditional recipe that calls for frying. You can use any salsa that you have slightly warmed or a typical tomato sauce to go with your chiles rellenos. I'm sharing an easy Fire Roasted Tomato Sauce that I think works nicely with this dish.
Don't forget to play mariachi music and put a basket of tortilla chips on the table when you serve these to your family. *