Preheat oven to 275.
Cut cherry or other small meaty tomatoes in half, and large ones in half slices. Place on a foil-lined baking sheet. Drizzle with olive oil, salt and sugar. Toss well. Flatten to single layer. Bake for 2-4 hours until dried out and a bit shriveled. Cool and place in a jar with fresh oregano or basil and drizzle with additional olive oil. Seal and store in regrigerator. Let come to room temperature to use.
Watch the how-to video here.