Line your sheet pan completely with foil. Arrange the peppers on the pan in a single layer. They should be dry, with no oil added to them.
Set your oven rack to the highest setting, close to the broiler.* Broil the peppers until they blacken on one side. Then remove the pan, flip them over, and broil again until blackened. Keep a close eye on them as they will blacken quickly.
Remove the pan from the oven and cover with a heavy duty plastic wrap to allow the peppers to steam for 15 minutes. Note: if you're not comfortable covering the hot pan with plastic wrap you can place the chiles right into a heavy duty zip lock baggie or paper bag and seal it up to steam them. You just need an environment that will hold in the steam.
Remove the plastic and de-stem and de-seed your peppers. You can use a spoon to scrape out the seeds, they'll come out easily. Don't worry about getting every last one, they're perfectly edible.
Give the peppers a rough chop and put into a blender along with the stock, water, olive oil. lime juice, garlic, and salt. Blend until smooth.
Taste the sauce and adjust the seasoning as you like. Use immediately or transfer to an airtight container and refrigerate for up to a week. Freeze for longer storage.
Notes
*Position Your Oven Rack Safely: place the oven rack at a safe distance from the broiler element. This will help control the intensity of the heat and reduce the risk of sudden flaring. If any of your peppers are too close to the broiler at the highest setting, then lower your rack one rung.
Nutritional information is provided as a courtesy and is an estimate only. This information comes from online calculators. Although The View from Great Island attempts to provide accurate nutritional information, these figures are only estimates.
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