When is it done? Try this test: When the liquid has reduced by two-thirds, drop a spoonful onto a chilled plate and drag your finger through; if the jelly holds a trail that doesn't fill back in, it's ready. Learn more in this video on the Bon Appetit website.
Sweet and Spicy Chile Pepper Jelly
Makes about 3 cups
4 red bell peppers, coarsely chopped
2 red chiles (such as Fresno), coarsely chopped
3 cups sugar
1½ cups apple cider vinegar
Pulse bell peppers and chiles in a food processor until very finely chopped (be careful not to purée). Transfer to a large saucepan and add sugar and vinegar. Bring to a boil, reduce heat, and simmer until liquid is reduced by two-thirds, about 1 hour.
Transfer jelly to heatproof jars; cover and chill until set, about 4 hours.
Jelly can be made 2 weeks ahead. Keep chilled.
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