1. Rinse chilies and cut off stem ends. Wearing gloves or holding chilies with a fork (do not touch with bare hands), cut chilies in half lengthwise. Slice out and discard veins and seeds. Cut chilies into 1/8- to 1/6-inch slivers.
2. Put chilies, vinegar, and sugar in a 4- to 5-quart pan. Bring to a boil over high heat, stirring often, and boil until mixture is reduced to about 1/3 cup, about 7 minutes.
3. Scrape jelly from jars into pan. Stirring often, boil until jelly melts. Ladle hot jelly back into the unwashed jars to within 1/4 inch of rims. Wipe rims clean and screw lids onto jars. (If there is a little extra jelly, pour into a small dish and cover when cool.)
4. After 1 1/2 hours, gently shake jelly in jars to redistribute chili pieces if they have floated to the top. When jelly is cool, use or store in the refrigerator up to 3 months.
Nutritional analysis per tablespoon.