Wash tomatoes, but don't dry them. Slice thinly, collecting all the juice in a bowl as slice.
Arrange the sliced tomatoes in the same bowl in layers, sprinkling each layer with sea salt.
Place another bowl or plate directly on top on the tomatoes and weight it down. Leave to marinate for 5 hours.
Drain thoroughly.
Add white wine vinegar to cover tomatoes and leave again for another 4 hours, then drain again.
Layer tomatoes in jars sprinkling each layer with some garlic, fennel seeds, oregano, and a few drops of the balsamic. Distribute the chili peppers here and there throughout the jars.
Pour olive oil over the tomatoes, shaking the jar to remove any air pockets.
Cover tightly and store in a cool place. These tomatoes can be eaten after 5 days, but it will last for 5 months.
