Baked Beef Chiles Rellenos Casserole

Ingredients
6 large poblano peppers, halved and seeded
1 ½ pounds ground beef, or to taste
1 tablespoon chili powder
2 cloves garlic, minced
1 teaspoon ground cumin
1 teaspoon dried oregano
¼ teaspoon ground cayenne pepper
¼ teaspoon ground paprika
¼ teaspoon ground dried chipotle pepper
salt and ground black pepper to taste
1 large onion, chopped
2 (14.5 ounce) cans diced tomatoes with green chile peppers
cooking spray
3 cups shredded Mexican cheese blend, or to taste
Directions