In a large pot, bring Cider Vinegar, Sugar, Garlic Powder, Cayenne, and Celery Seed to a boil.
Reduce heat and simmer for 5 minutes.
Add the Jalapeno Pepper Slices (and Red Bell Pepper, if desired) and simmer for 4 minutes.
Use a slotted spoon to transfer the Peppers into clean, sterile canning jars, packing the Jalapenos semi-firmly within 1/4 inch of the rim of the jar.
Turn heat up for the remining syrup and bring to a full rolling boil.
Boil for 5 minutes.
Use a ladle to pour the boiling syrup into the jars over the Jalapeno Slices.
Insert a knife into each of the jars 2-3 times to release any trapped pockets of air.
Add more syrup if necessary.
Wipe the rims of the jars with a clean, damp paper towel then screw on two-part canniong lids.
If you do NOT want to properly cans these, simply cool jars at room temperature for an hour and then store them in a sealed container in the fridge for up to 3 months.
Use proper canning procedures to store at room temperature for longer periods of time.
To can, place jars in a canner and cover with water by 2 inches. Bring the water to a full rolling boil. When it reaches a boil, set the timer for 10 minutes for half-pint jars or 15 minutes for pint jars. When the timer goes off, use canning tongs to transfer jars to a cooling rack or kitchen towel. Leave them to cool, undisturbed for 24 hours. When fully cooled, wipe them with a clean damp washcloth. Double check that they have sealed properly down on the center of the lid. It will not move if sealed.