Prep the peppers: Wash peppers and slice into ¼” thick slices, if desired.
Prepare the pickling jar: Add cut peppers to a tall jar and add cilantro or other desired herbs, mustard seeds, garlic, and red pepper flakes.
Prepare and add the brine: In a medium saucepan bring the water, vinegar, salt, and sugar to a boil. Once boiling, pour into the jar until the liquid completely submerges the peppers. Close the lid on the jar tightly.
Pickling instructions: Let the jar cool on the counter until it reaches room temperature. Once cooled, put the jar into the refrigerator and let the peppers pickle for at least 4 hours before serving, but for best results serve after at least 24 hours. Quick pickled peppers are good up to 2-3 months in the refrigerator.
Which vinegar should you choose? White vinegar, white wine vinegar, and apple cider vinegar are the best vinegar choices for pickling peppers.
Recommended jar: Because peppers are a tall vegetable if pickling whole, choose a tall jar so they fit snug with about ½ - 1 inch space (2-3 cm) below the lid.
Other recommended tools: small saucepan, cutting board, knife set
Prep ahead and storage: Refrigerator pickled peppers should be made at least 4 hours before serving, but for best results make at least 24-48 hours ahead. Keep pickled peppers refrigerated and they can be enjoyed for up to 2-3 months. Do not freeze pickled peppers.
Nutrition notes: This recipe uses only plant-based ingredients and it is gluten-free. It does call for a high amount of salt for the brine, however the amount actually absorbed by the peppers themselves is small compared to the amount of salt used in the recipe.