To roast peppers over an open flame, turn a gas flame to HIGH. Arrange pepper directly over the flame. Using tongs, turn the peppers occasionally until all sides are blackened and blistered but not ash white. Alternatively, you could roast in a 400º oven for 40-50 minutes.
Transfer to a bowl and cover tightly with plastic wrap. Let stand until peppers are cool enough to handle, about 20 minutes. Peel the blackened skin off of the pepper and discard along with the stem.
Add the roasted hatch chile along with the rest of the ingredients into your food processor. Pulse until all of the ingredients are well combined.
Serve over any grilled meat or use as a marinade. I also love it tossed with hot crispy potatoes.