Heat small saucepan over medium high heat.
Add vinegar, sugar, and mustard seed, salt to the pan and cook until it begins to simmer and sugar dissolves. Stir in jalapeno peppers and garlic, boil for a minute and remove from heat.
Let mixture cool for 10 minutes.
Boiling garlic is a blanching process which will keep the garlic from turning blue in the pickle jar.
Sterilize the jars, lids, and rings in boiling water for at least 5 minutes.
Toss the dill, chillies, bay leaf, and 1 inch sliced cucumbers and slice onion together in a heat-proof sterile jar.
Pour in simmering liquid already combined with garlic and peppers over the sliced cucumbers and onions, dill leaves, halved chillies and bay leaves in the bottle and stir.
If liquid is not enough to submerge vegetables and spices then add water to adjust the amount so that it covers the mixture in jars.
Close the jars and refrigerate overnight or for up to 1 month.