Drying is a traditional Italian way to preserve an abundance of ripe summer tomatoes so that they can be enjoyed throughout the rest of the year, particularly in the southern Italian regions of Calabria and Puglia. Every year, my ex-boyfriend's mother in Puglia would spread sheet pans full of halved tomatoes on the roof of their house to dry for several days in the blazing-hot Pugliese sun.
Many people, particularly outside Italy, have not tasted the homemade version; before I did, I used to think I was not really a fan, because even though I love tomatoes, the store-bought sun-dried tomatoes I had tasted were a bit leathery and tough, with not much flavor. They seemed like a faded, desiccated memory of a tomato, rather than a fragrant, intensified taste of summer days.
Homemade sun-dried tomatoes are another thing entirely: fragrant and chewy but not tough, with complex, concentrated tomato flavor and a slight sweetness.
Although it's not difficult, the trouble with making them at home is that many of us do not have the abundant outdoor space required, or the time, or perhaps we lack consistent, strong sunshine, or live in highly polluted cities or bug-infested areas where perhaps drying food outdoors is not the best idea.
The solution? You can easily dry them in your oven. For large quantities, you'll need to do this in batches; you should be able to fit about 2 pounds of tomato halves on a large baking sheet per batch. Once they are properly dried, they will last for many months in zipper-sealed plastic bags stored in a cool, dry place.
When you're ready to use them, you can use them directly in any recipe that calls for them, or do as my ex's mother would and marinate them in a jar full of olive oil and spices (Click here for the Recipe for Sun-Dried Tomatoes in Olive Oil). They are great as pizza toppings or in pasta sauces, in salads or simply as-is, as part of an antipasto platter.
Preheat the oven to 200 degrees F (100 degrees C), or the lowest setting possible. Resist the temptation to use a higher temperature to speed up the process, as then you'd be cooking the tomatoes, instead of drying them.
Core the tomatoes and cut them in half lengthwise (from stem end to tip). Squeeze each half gently over a bowl to remove excess liquid and seeds. Make a small slit with the tip of a sharp paring knife in the back (peel side) of each tomato half, to help them dry.
Place a drying rack on an aluminum foil-lined baking sheet and arrange the tomatoes, cut side up, in a single layer on the rack. Make sure there is a bit of space around each tomato and that they're not touching, so they can dry evenly.
Lightly sprinkle the tomatoes with salt (and dried herbs, if using).
Place in the oven and bake until the tomatoes are completely dry and a bit leathery, but not hard, brittle or crispy. They should still be somewhat chewy and flexible. Check them every hour during drying. Depending on your tomatoes and oven, this can take anywhere from about 6 to 12 hours.