Step 1

Trim and thinly slice 8 ounces medium jalapeños crosswise.

Step 2

Place 1 cup granulated sugar, 1/2 cup apple cider vinegar, 1 teaspoon yellow or brown mustard seeds, 1/4 teaspoon celery seeds, 1/4 teaspoon ground turmeric, and 1/4 teaspoon kosher salt in a small saucepan. Bring to a boil over medium heat, stirring occasionally until the sugar dissolves, about 4 minutes.

Step 3

Add the jalapeños and boil, stirring frequently, until they are shiny and slightly shriveled, 4 to 5 minutes. Using a slotted spoon, transfer the jalapeños to a glass pint jar.

Step 4

Continue boiling the vinegar mixture until syrupy and reduced by about 1/3, 5 to 10 minutes. Pour the syrup over the jalapeños and press down on them to make sure they are fully submerged. Let cool to room temperature. Serve or seal the jar and refrigerate for up to 3 weeks.