Oil them up. Cover a baking sheet with tin foil. Spread the chiles out over the baking sheet. Drizzle them with a just a little bit of olive oil and toss to coat.
Roast them. Place the baking sheet in the oven and broil the chiles for 5-7 minutes. Flip them over with tongs and broil them for another 5-7 minutes.
Peel them. Once both sides of the chiles have charred, remove them from the oven and set them aside to cool. When the chiles have cooled, peel them and slice them open, discarding the seeds.
Chop them. Roughly chop the chiles and store them in the fridge within two hours. Hatch chiles can be stored in the freezer for up to a year; in the fridge, they’re good for about three days.