Place Anaheim peppers on a baking sheet and bake about 20-25 minutes, flipping once through, or until the skins become charred and puffy. Or, you can char them over open flame on the stovetop.
Remove from heat and cool slightly, then place into a plastic baggie to steam for several minutes. Once cooled enough, peel off the skins and discard. Set the peppers aside until ready to use.
While peppers are baking, heat an oven proof pan to medium heat and add olive oil.
Season chicken breast with Creole seasonings, salt and pepper. Sear the chicken on each side 3-4 minutes to blacken. Add about 1/4 cup of water or chicken stock to the pan and allow to steam.
Set the pan into the oven at 400 degrees F. and bake 8-10 minutes, or until chicken is cooked through. Remove.
Shred or chop the chicken and place into a mixing bowl.
While the chicken is baking, cook the onion in the same pan, about 5 minutes, or until softened. Add garlic and cook 1 more minute, stirring. Remove from heat and add to mixing bowl with chicken.
To the mixing bowl, add feta cheese and oregano. Mix well.
Slit each pepper down the center and scoop out the insides.
Spoon the chicken-cheese mixture into the peppers and set them into a baking dish.
Bake for 15 minutes.
Remove from heat and set onto serving plates.
Slice the lemons and squeeze lemon juice over the stuffed peppers.
Top with cilantro and hot sauce, if desired.
Heat Factor: Mild. Anaheim peppers are quite low on the heat scale. You can easily add in some hotter chopped peppers when you cook the chicken with the onion, or use a spicy Creole or Cajun seasoning blend.