Washington Post, a simple recipe attempting to replicate chile rellenos (poblano chilis stuffed with cheese and served in sauce) as a casserole. Other than the fact that chili rellenos typically are breaded and fried before covering with sauce, this sounds reasonable. The recipe actually calls for canned poblanos which I doubt I could find but also includes instructions on roasting fresh ones. It's really not hard to roast chili peppers, I have several recipes that call for it. The recipe also says it can be "halved". The recipe is already pretty small, made in a 9" square casserole, whyever would you halve it?.
The description of the recipe tells where they got it. On Christmas eve a woman named Lynda Finch spent all day cooking for her family's Christmas meal. One dish was this recipe, which she assembled and put it in the refrigerator unbaked for the next day, leaving the recipe on the countertop next to the oven. That night Lynda died in her sleep. Her family gathered on Christmas day now to grieve instead of celebrate, but in their grief went ahead and finished baking the dishes she had prepared, believing they were a last gift to her three sons and their families.
Ingredients
1 pound ground beef, preferably 90/10 blend
1 cup (4 ounces) chopped yellow onion
2 teaspoons ground cumin
1 teaspoon fine salt, divided
3/4 teaspoon freshly ground black pepper
Unsalted butter, for greasing
1 (27 1/2 ounce) can whole poblano peppers, drained (may substitute 6 large fresh poblanos; see NOTE)
2 cups (8 ounces) shredded cheddar cheese
1/4 cup all-purpose flour
1 1/2 cups (350 milliliters) whole milk
4 large eggs, beaten
Instructions
1. Position a rack in the middle of the oven and preheat to 375 degrees. In a large skillet over medium-high heat, cook the beef and onions, breaking up the meat with a wooden spoon and browning the beef until it just starts to turn crispy, about 10 minutes. Using a slotted spoon, transfer the beef mixture to a medium bowl, leaving behind as much fat as possible in the pan. Season the mixture with the cumin, 3/4 teaspoon of the salt and the black pepper.
2. Grease a 9-inch square baking dish with the butter or the fat rendered from the beef. Gently remove the stems and seeds from the poblanos and open the peppers so the flesh lies flat. Line the bottom of the pan with the poblanos, skin side down, overlapping them some to cover completely. Chop any remaining poblanos and set aside. Layer the meat-onion mixture over the whole poblanos and top with the shredded cheese and reserved chopped peppers.
3. In a medium bowl, whisk together the flour and the remaining 1/4 teaspoon of salt. While whisking, gradually pour in the milk, breaking up any clumps of flour. Whisk in the eggs and evenly pour the mixture into the baking dish.
4. Bake the casserole for 45 minutes, or until it has puffed and browned. Remove from the oven and serve.
NOTE: To use fresh rather than canned poblanos, position an oven rack 4 to 6 inches from the oven’s broiler element; preheat to broil. Place the poblanos on a large, rimmed baking sheet and broil until they brown in spots and blister without charring, watching them carefully and turning them with tongs until they are blistered all over. Transfer them to a heatproof bowl and cover with a plate or pan lid to let them steam and cool enough to be handled, at least 10 minutes. When the poblanos are cool enough to handle, use your fingers to carefully remove and discard their skins. Make a vertical slit from the stem end to the tip of each pepper. Gently remove the seeds and stems and open the peppers so the flesh lies flat.