Make sauce: Preheat oven to 350 degrees. Peel away the dry husk and rinse the tomatillos. Chop them in half and set them skin sides up onto a lightly oiled baking sheet. Slice all of the peppers in half lengthwise and set them onto the baking sheet. You might need more than one sheet. Also, remove the innards of the poblano before placing them. Add the garlic to the baking sheet and bake for 20-30 minutes, or until the pepper skins are nice and charred. You can also broil them, but don’t set them too close to the heat source. Remove from heat and let everything cool a bit. Peel the skins from the peppers, if desired, and add to a food processor with tomatillos. Squeeze the garlic from their skins and into the food processor they go. Add cilantro, cumin, chili powder and salt and pepper. Process to combine. Add chicken broth and lime juice and process until smooth. Pour the green enchilada sauce into a pan or a pot and simmer for 5-10 minutes or so to let the flavors fully develop.
Preheat the oven to 375 degrees. Coat a 9”x13” pan with cooking spray.
In a medium bowl, mix together the monterey jack and cheddar cheeses.
In a large bowl, mix together the chicken, 1/2 of the cheese, green chilies, garlic powder, cumin, onion powder and salt and pepper to taste.
Stack the tortillas on a plate and wrap with a damp paper towel. Microwave for 1 minute until tortillas are warm and pliable.
Lay one of the tortillas on a flat surface and spread approximately 2 teaspoons of sour cream down the center of each tortilla. Add approximately 1/3 cup of the chicken mixture, then tightly roll up the tortilla and place it seam side down in the pan.
Repeat the process with the remaining tortillas.
Pour the enchilada sauce over the top of the pan, the top the enchiladas with the remaining cheese.
Bake for 20 minutes or until cheese is melted. Serve, topped with chopped cilantro and tomatoes if desired.