I spent the day with my good friend Jeremy pickling and canning some late in the season produce from Green City Market. We also decided to pickle some mackerel because its customary to can fish late in Autumn. I have never canned anything before, so there was a bit of a learning crurve. Canning can be dangerous if done wrong. If the jars aren't completely sanitized there is a chance of botchalism. The best way of sanitizing the jars is by soaking them in soapy hot water, then boiling them for 10 minutes. Air dry the jars upside down on a towel until ready to fill. Jeremy began by filleting mackerel, then cutting it into small cubes leaving the skin on. Mackerel has a very thin skin so it is edible. Then he marinated the fish in a brine of 1 cup of apple cider vinegar , 1 cup of water, 1/4 cup salt, 1/4 cup sugar and fresh black pepper to taste. After about 10 minutes he removed the fish from the brine and placed it into the sanitized jar with fresh dill. He heated the brine until very hot then added it to the jar. The last step was to soak the jar in boiling hot water for 20 minutes. The lid should "pop", assuring that you have securely sealed the lid.