This is sort of traditional with a twist and it's time consuming but not if you break down the tasks.
I'd put this in the cookbook but measurements are approximate.
I used Poblano Chilis. Available seasonally in the UK from:
http://www.southdevonchillifarm.co.uk/Other than that you'd have to buy a tin of whole chilis from somewhere or have it sent from the USA.
12 Poblano/Anaheim Chilis (I guess you could use narrow green peppers in a pinch though it won't be the same)
12 1 cm x 4 cm chunks of Over the Moon brand Mexican Cheddar Cheese
12 1 cm x 4 cm chunks of Welsh Monteray Jack Cheese (Sainsbury's deli)
3 eggs
4 tablespoons (more or less) of plain flour
2 to 3 cups of Panko (Japanese Bread crumbs available at your local Asian store) -you can use bread crumbs here or cracker crumbs or what ever)
Salt/Pepper to taste.
Light oil for frying.
Okay.
First mission if using nice real chili peppers is to roast them.
Turn your grill onto high and put all the peppers on a tray. Keep the tray about 5 inches from the top. Grill the peppers until the skins gets mostly black. (Now you don't want to burn the pepper, but just singe the skin.) Keep watching them and turning them as they singe. Once you have an overall even blackened skin -take the peppers out and either shove them in a plastic bag or a Tupperware. Let them steam in there for a good 15 minutes or so. Carefully peel the cracked and blackened skins off the peppers. You have to be very patient or will wind up ripping the whole pepper open. Some will tear a bit but don't worry use that whole to put in the cheese. I left the little top on, but some just fell off -no worries either way. Next you must clean out the seeds. . Gently turn out the lid of the pepper and use your finger to begin to deseed it. if you must you can also rinse out the seeds quickly, but make sure you squeeze out the water and don't use too much or you loose some flavour. Set aside and repear until al chilis are done.
I usually do this part the day before or a few hours before. Relax a bit now. Have some wine... read a book.
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If using tinned whole green chilis.. open tin.
Right. The cooking process.
Take your lovely cheeses and use whatever hole is there to put the cheese inside the pepper.. don't worry if you get an extra hole or it's not perfect. Just keep the cheese covered by pepper.
Crack eggs and if desired separate them . Whip the egg whites until frothy and getting stiff and then mix back in with the yolks and flour. Or just forget that part and mix it together to begin with. Season with salt and pepper.
Place breads crumbs on a piece of parchment/baking paper (a lot less fuss).
Place oil in pan and heat up. you should have at least an inch of oil.
Next carefully take the pepper and dip into batter. Coat well and then place and cover in bread crumbs.
Place into hot oil and fry on one side and then flip and fry on the other. Key is to get them golden brown. Your oil needs to be hot or what you will get is melted goopy cheese and greasy flat peppers. Think that everything is cooked already so really only a few minutes is needed.
I normally drain the peppers on the grill pan and keep them in the oven at about 50C to keep warm.
Repeat with the rest of the peppers.
Serve with sour cream, guacamole, salsa or a enchilada type chili sauce.
It's a bit PIA but oh so good...
The other traditional way to make them is to just beat 4 to 5 egg whites until just starting to stiffen, and then dredge the chilis in that and then fry them. I find they are a bit too eggy for me this way and get soggy. I like the nice crunch of the bread crumbs. I also really advise people find panko as it makes the best coating for everything from chicken to fish to veggies.
Let me know if you have any questions.
Oh and watch out for the peppers near the top where the seeds were.. bit um hot!
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and please when de-seeding don't stick those fingers near any where important!
Also you can just use cheddar or fresh cheese like a Mexican type queso blanco.
Now who says you can't get good Mexican here?
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