Cut the stems off and slice into ¼” thick rounds. Discard any seeds that fall out during cutting.
In a pot or saucepan, combine the vinegar, sugar, and all the spices. Heat over medium, stirring until all the sugar is dissolved.
Add the sliced jalapenos and return to the heat, cooking for 12-15 minutes until the jalapenos are soft and have started to absorb the sugar.
Strain the jalapenos into the prepared glass jar using a slotted spoon, leaving the liquid in the pot.
If you would like to remove some of the seasonings remove them with a fine mesh strainer at this point.
Return the liquid to medium heat and bring to a boil. Cook for an additional 7-10 minutes until the liquid has reduced by half and is a very thick syrup.
Pour the syrup over the jalapenos and place the lid on. Allow to cool before eating.
Store in the fridge for up to 2 weeks.
Notes
Take care when cutting a large amount of peppers. To prevent any burning on your hands, wear gloves.