Hot-pack method
Wear gloves when handling hot peppers. Wash and dry them, then slit each pepper so steam can escape. Blister skins in a 400°F oven or under a broiler for 6–8 minutes. Let cool under a damp cloth; peel, discard seeds and chop. This is the pepper-preparation method referenced by NCHFP; use the Chile Salsa formulation and processing schedule below.
Wash tomatoes. Dip them in boiling water for 30 to 60 seconds or until the skins split, then dip in cold water. Slip off skins, remove cores, and coarsely chop.
Combine tomatoes, prepared chile peppers, onions, 5% vinegar, salt, and pepper. Bring to a boil and simmer for 10 minutes.
Fill hot pint jars with hot salsa, leaving 1/2-inch headspace. Remove air bubbles, adjust headspace, wipe rims, and apply two-piece lids.
Process pints in a boiling-water canner for 15 minutes at 0–1,000 feet, 20 minutes at 1,001–6,000 feet, or 25 minutes above 6,000 feet. Cool undisturbed for 12 to 24 hours and check seals.