• Preheat the oven to 250 °F. Position the oven rack in the center of oven.

  Line a baking sheet with parchment paper or silpat mat
• Wash the tomatoes and pat dry. Slice the tomatoes in half (from stem to end).

  Put the tomatoes in a large bowl and toss gently with the olive oil, and sea salt.

  Place the tomatoes cut side up, in a single layer, on the baking sheet.
• Bake for 1 hour, rotate the tray, add herbs now if using, and bake for an additional 30-60 minutes.

  Baking times will vary based on the actual size of the tomatoes. Larger tomatoes, such as Roma's, can take up to 3.5 hours in total. Cherry tomatoes can take as little as one hour.
• The tomatoes are done when they are dried but still soft and flexible. If there are smaller tomatoes be sure to remove them toward the end of the cooking time to be sure that they don't burn.
• Remove from the oven and allow to cool completely on the tray.
• If not using immediately, store tightly sealed in the refrigerator for up to 1 week.

  Alternately, pack the cooled tomatoes in jars and submerge them with olive oil (and more herbs if desired), and store, sealed, in the refrigerator for up to 3 months.

Adding seasoning:

• If planning to add seasonings while cooking, such as dried herbs or spices, sprinkle them on the tomatoes around the 1-hour cooking mark.