Prep the chilies: Wash the green chilies well.
Dry them completely with a clean cloth.
Use a toothpick or fork to prick each chili 2–3 times (this helps salt and buttermilk penetrate).
Salt soak: In a mixing bowl, combine chilies and sea salt. Toss to coat evenly.
Leave them covered in a bowl or jar for 1–2 days. Stir once or twice a day to help the salt draw out moisture.
Buttermilk soak: After 1–2 days, pour in the buttermilk so the chilies are fully submerged.
Cover loosely (cloth or lid) and keep at room temperature for 2–3 days. The buttermilk will ferment slightly, giving a tangy taste.
Drying: Remove the chilies from buttermilk, shaking off excess liquid.
Spread them out on a clean cloth or large plate.
Sun-dry for 5–7 days (or longer if needed) until they become fully dry, crisp, and leathery. Bring them in at night to avoid moisture.
Storage: Store the dried chilies in an airtight jar. They keep well for 6 months or longer.