Cooks' Note
To roast corn: Preheat the oven to 425°F. Remove the silks from the corn, but leave the husks on. Soak in cold water for 10 minutes. Drain the corn, place on baking sheets, and roast in the oven until tender and slightly charred, 15 to 20 minutes. Let cool slightly; then remove the husks and slice off the kernels, letting them fall into a bowl.
To roast chiles: Preheat the oven to 400°F. Brush the chiles with canola oil and season them with salt and pepper. Place them on a rimmed baking sheet and roast in the oven, rotating them occasionally, until charred on all sides, about 30 minutes. Remove from the oven. Transfer to a bowl, cover with plastic wrap, and let sit for 15 minutes to allow the skin to loosen. Then peel, halve, and seed.
