Pick out young heads of garlic and remove their outer layers. If they are too large, divide them. Parboil them with boiling water and then immediately rinse under running cold water.
Arrange the garlic in jars, and throw in dill sprigs if desired. Fill each jar 2/3 of the way up with vinegar, add the salt, sugar and fill up the rest of the jar with hot water. This is done in order to measure exactly how much brine you will need.
Transfer the liquid from the jars into a pot and bring it to a boil for a few minutes. Then pour it back over the garlic in the jars. Put 1 aspirin in each, place warm caps on them and turn them upside down for 12 hours.
Keep flipping the jars over for 3 more days, at which point the pickled garlic will be ready for consumption.