Preheat your oven's broiler and place the rack about 6 inches from the heat source. Line a baking sheet with aluminum foil and place the poblano peppers on it. Broil for 5-7 minutes per side, turning occasionally, until the skins are blackened and blistered.

Transfer the roasted peppers to a bowl and cover tightly with plastic wrap or foil. Let them steam for 10 minutes. Once cool enough to handle, peel off the charred skin, cut a slit down one side of each pepper, and remove the seeds and stems.

Preheat the oven to 375°F (190°C). Grease a 9x13-inch casserole dish with cooking spray or olive oil.

Lay half of the roasted peppers in a single layer on the bottom of the dish. Sprinkle 2 cups of Monterey Jack cheese evenly over the peppers. Repeat with the remaining peppers and 2 more cups of cheese to create a second layer.

In a medium bowl, whisk together the eggs, milk, flour, baking powder, garlic powder, onion powder, oregano, salt, and black pepper until smooth and well combined.

Pour the egg mixture evenly over the layered peppers and cheese, ensuring it seeps into all the crevices.

Place the casserole in the preheated oven and bake for 40-45 minutes, or until the center is set and the edges are golden brown.

Let the casserole rest for 10 minutes before slicing. Serve with sour cream, salsa, or chopped cilantro, if desired. Enjoy!