Roast the poblanos under your broiler or on the grill until well charred, turning to get all sides good and roasted.
Remove from heat and let cool until you can handle them.
Remove the charred skins and seeds. Do not rinse them in water or you'll loose all the great roasted flavor.
Cut the peppers into rings (some of my peppers exploded, so I ended up with pepper bites instead of rings).
Heat oil in a deep fryer or deep pan to 350 F.
Arrange 3 shallow bowls.
In the first place the flour and stir in a few pinches of salt.
In the second bowl, crack the eggs and scramble them with a fork or whisk.
The last bowl is for the panko and cayenne. Just stir them together.
Working in batches, dip the poblano rings into the flour and coat.
Shake off any excess flour, then dip them into the eggs. Coat well.
Shake off any excess egg, and dip into the panko mixture. Coat well.
Slowly add the poblanos to the oil. Fry them until golden and crispy on the one side, 2-4 minutes, then flip and fry on the other side for about the same amount of time.
Remove to a paper towel-lined plate and sprinkle with salt.