Preheat the oven to 350 degrees F (175 degrees C).
Spray a 9x13-inch casserole dish with cooking spray.
Cook and stir ground beef in a Dutch oven over medium-high heat until meat starts to brown and release juices, about 5 minutes.
Reduce heat to medium and stir in poblano peppers, salt, salsa, oregano, and chipotle powder; cook and stir until seasoned beef is crumbly and no longer pink, about 10 minutes.
Mix one package of corn muffin mix in a large bowl with 1 egg and 1/3 cup of milk. Whisk to combine. In a separate large bowl, mix the second package of corn muffin mix with 1 egg, 1/3 cup of milk and half the Cheddar and Monterey Jack cheeses.
Spread the prepared corn muffin mixture without cheese into the prepared baking dish. Sprinkle corn over the muffin mix, followed by remaining half of the cheeses, then the beef mixture.
Spoon the corn muffin mix with cheese on top of the beef and carefully spread over the top with a fork, leaving about half an inch from the edges of the pan.
Bake in the preheated oven for 50-60 minutes, until golden brown.
