You only need eight ingredients—canned whole poblano peppers, Monterey Jack and Cheddar cheeses, eggs, evaporated milk, all-purpose flour, milk, and enchilada or tomato sauce—to make the recipe.

I have never been able to make chile rellenos. I know how — in theory — but I’ve never succeeded. I will char my poblano peppers, steam them to get the skin loose, then peel them. Cut open the peppers ...