Slice jalapenos and add the carrots, peppers and onions. Mix cider vinegar, sugar, mustard seed and garlic in a medium stainless steel pot, bringing to a slow boil.
Reduce for 5 minutes to a simmer. Add jalapenos and other veggies and continue at the simmer for 5 minutes more.
Load sterilized jars with jalapenos and veggie mixture first and then add liquid filling the jars leaving a 1/4 headspace. Remove air and refill if necessary. Wipe rim, add hot lids/rings and process in a water bath for 15 minutes.
Makes 7 half pints.