Preheat oven to 400 degrees F.
Heat oil in a large cast iron skillet over medium heat. Add the poblano, onion, garlic, salt and pepper and cook, stirring, until tender, about 5 minutes. Set aside.
Meanwhile, In a medium bowl combine the corn meal, GF flour, baking powder and coconut sugar. Stir to combine.
In a separate bowl, combine the egg, canned corn, can green chiles, sour cream and milk. Using a fork, whisk until well combined.
Pour the wet corn mixture into the bowl with the dry cornmeal mix. Using a rubber spatula or wooden spoon, stir until very well combined. (don't overbeat it though)
Pour the cornbread mix into the cast iron skillet with the onions and poblanos. Carefully toss the mixture until well combined. Spread the cornbread across the skillet into an even layer.
Transfer to the oven and let bake, uncovered, until set and golden brown on top, about 20 munutes.
Remove from oven and let cool for 10 minutes before slicing and serving!
Enjoy! (refrigerate leftovers!)