Preheat your oven to 375°F (190°C). Lightly grease a 9x13 inch baking dish and set aside. This preparation ensures your peppers won't stick and makes cleanup easier after baking.

Roast the poblano peppers using your preferred method. You can place them directly over a gas flame, under a broiler, or on a baking sheet drizzled with a little olive oil, turning until the skins are charred and blistered. Transfer the charred peppers to a bowl, cover tightly with plastic wrap, and let steam for 10-15 minutes. This steaming process helps loosen the skins for easy peeling.

Once cooled enough to handle, carefully peel off the charred skins from the poblanos. Make a slit lengthwise down each pepper, remove the seeds and membranes, being careful to keep the peppers as whole as possible for stuffing. Set the prepared peppers aside.

While the peppers cool, heat 1 tablespoon of olive oil in a large skillet over medium heat. Add the diced onion and cook, stirring occasionally, until it softens and becomes translucent, which usually takes about 5 minutes. Stir in the minced garlic and cook for another minute until fragrant.

Add the ground beef to the skillet with the onion and garlic. Cook, breaking it apart with a spoon, until it is browned and crumbly, which typically takes 5 to 7 minutes. Drain any excess grease from the skillet to prevent a greasy final product.

Stir in the chili powder, ground cumin, smoked paprika, dried oregano, ½ teaspoon of salt, and ¼ teaspoon of black pepper into the beef mixture. Cook for 1-2 minutes, allowing the spices to toast and become fragrant. Taste and adjust seasonings as needed for your preference.

Lay the prepared poblano peppers flat in your baking dish. Evenly divide the ground beef mixture among the peppers, stuffing them generously. On top of the beef, layer the thin slices of Monterey Jack and sharp Cheddar cheese.

Pour the enchilada sauce evenly over the stuffed poblano peppers, ensuring they are well-coated. Cover the baking dish tightly with aluminum foil to help steam the peppers and melt the cheese effectively.

Bake in the preheated oven for 15 minutes. After 15 minutes, remove the foil and sprinkle the remaining ¼ cup of shredded sharp Cheddar cheese over the top of the peppers. This adds a beautiful golden crust.

Continue baking uncovered for another 45 minutes, or until the peppers are tender, the cheese is bubbly and melted, and the sauce is fragrant. The additional baking time allows the flavors to meld beautifully.

Carefully remove the baking dish from the oven. Let the stuffed poblano peppers rest for 5-10 minutes before serving. Garnish with fresh chopped cilantro, if desired, for a burst of color and freshness.