Prepare the eggplant the evening before. Cut the ends off the eggplants and peel. Cut the peeled eggplant into long strips about as big around as shoestring chips. Place the strips into a large bowl and stir in 1/2 cup of coarse salt.
Place a sturdy dinner plate upside down in the sink making sure that the drain is not blocked. Place a generous handful of the eggplant strips onto the centre of the plate and cover with another upside down dinner plate to create an eggplant sandwich. Layer more eggplant and plates until all of the eggplant is sandwiched. Cap it off with one additional plate and press down firmly. Set a sturdy saucepan on top and fill with enough water to create some pressure on the eggplant layers. Not so much pressure that you break your dishes though. Let this pressing process stand overnight.
The next day fill a large bowl with ice water. Begin dismantling your stack of plates. One layer (handful) at a time, briefly swish the eggplant around in the ice water then squeeze dry and place into a clean bowl. If your hand starts to hurt you are swishing too long. Once all of the eggplant is rinsed and squeezed and in the bowl mix in the vinegar. Let rest for about 15 minutes.
Heat a splash of the olive oil in a frypan over medium heat. Once the oil is hot add the garlic, chilli flakes, oregano and sea salt. Cook and stir just until fragrant. You do not want to cook the garlic. Set aside to cool.
Your eggplants should be well rested now. Give them one last squeeze. Make it a good one or your melenzana is going to taste like pickles.
Place the squeezed eggplants into a large bowl and stir in the contents of the frypan and remaining olive oil until well blended. Transfer to sterile 500ml or 250ml jars. Make sure to fill the jars to the top and top off with any olive oil that may be left in the bowl. Wipe the rims with a clean dry cloth and seal tightly with new lids. Refrigerate for at least a month before opening.