Poblano Chile Gratin

Preheat the broiler. Place the poblano chiles on a small rimmed baking sheet. Broil for 10 to 15 minutes, turning the chiles occasionally, until charred on all sides. Remove from the oven and transfer them to a zip-top bag. Seal the bag and let them rest for about 20 minutes, until cool enough to handle. Peel the chiles, remove the seeds, and slice into thin strips.

Preheat the oven to 400°F and spray a large oval baking dish with non-stick cooking spray. Toss together the chiles, potatoes, onions, and half of the cheese and transfer to the prepared baking dish.

Whisk together the heavy cream and milk in a small bowl and season with salt and pepper, to taste. Pour evenly over the potato mixture. Sprinkle the remaining half of the cheese over the top.

Bake for 45 minutes to 1 hour, until the potatoes are tender. Remove from the oven and let it rest for 10 minutes before serving.