Prepare your canning equipment by sterilizing jars in boiling water.

Wash your jalapeños under cool running water and slice them into rings about 1/4 inch thick.

In a large saucepan, combine apple cider vinegar, brown sugar, red pepper flakes, minced garlic, mustard seeds, celery seeds, and turmeric. Heat over medium until the brown sugar dissolves, about 5 minutes.

Add the sliced jalapeños to the syrup and bring to a gentle boil. Cook for 10 minutes, stirring occasionally.

Using a jar lifter, remove a hot jar from the canning pot and place it on a clean kitchen towel.

Ladle the hot peppers and syrup into the jar, leaving 1/2 inch of headspace.

Use a bubble remover tool to eliminate air bubbles, then wipe the rim of the jar with a damp cloth.

Place canning lids on top and screw down the bands until finger-tight.

Process jars in boiling water bath for 10 minutes.

Carefully remove jars from water bath and place on a clean towel to cool completely.

Allow jars to cool for 12 to 24 hours before checking seals.