First Step: Roast the Poblano PeppersPreheat your oven to 450°F (230°C). Rinse and dry the poblano peppers thoroughly. Arrange them on a baking sheet lined with foil. Roast for 20–25 minutes, turning once after 10 minutes, until the skin becomes charred and blackened. Transfer the hot peppers to a sealed container or zip-top bag and let them steam for 15 minutes; this loosens the skin, making peeling easier.

Second Step: Peel and Prep PeppersOnce cooled, peel off the skin carefully. Cut each pepper in half lengthwise and remove seeds and membranes. Set aside the pepper halves for layering in the casserole. This step intensifies the mellow smoke flavor of the poblanos and ensures the casserole has tender, flavorful pepper pieces.

Third Step: Cook the Beef MixtureHeat a skillet over medium heat and add a drizzle of olive oil. Sauté the chopped onion and minced garlic until softened and fragrant, about 5 minutes. Add the ground beef, cumin, salt, and pepper. Cook thoroughly, breaking up the meat until fully browned. Drain excess fat to prevent greasiness, then return to heat briefly to warm the mixture.

Fourth Step: Assemble the CasseroleGrease a 9-inch (23 cm) baking dish with non-stick spray or butter. Lay the poblano halves flat-side down in a single layer across the dish bottom. Spread half of the cooked beef mixture evenly over the peppers. Sprinkle half of the combined shredded cheddar and Monterey Jack cheese over the beef. Repeat the layering with remaining peppers, beef, and cheese to build two layers.

Final Step: Bake and ServeBake the assembled casserole uncovered at 350°F (175°C) for 30–35 minutes until the cheese is melted, bubbly, and golden brown on top. Remove from oven and let it cool slightly before serving. This comforting Poblano pepper and cheese casserole pairs beautifully with sides like rice and beans, avocado salad, or crunchy tortilla chips for a complete meal.