How to Make It
Working in 2 batches, place cranberries and jalapeños in bowl of a food processor; pulse until cranberries and jalapeños are broken up, about 10 times. Transfer mixture to a large bowl. Stir in sugar and salt until dissolved. Transfer mixture to 1 or more jars with tight-fitting lids; loosely attach lids, and let stand 2 days at room temperature. Transfer jars to refrigerator, and continue to age at least 1 day or up to 12 days.
Before serving, return cranberry mixture to food processor, and pulse until mixture forms a chunky paste.