Arrange 3 oven racks to the top, middle and bottom positions of your oven. Line 3 rimmed baking sheets with parchment paper.
Rinse tomatoes and cut them in half crosswise (equator, instead of top to bottom) and arrange, cut side up, on prepared baking sheets.
Drizzle tomatoes with olive oil and sprinkle with fresh herbs. Sprinkle with salt to taste (I recommend a light sprinkle as the flavor will intensify).
Roast for 3 hours, until tomatoes are soft and shriveled. Rotate the sheets among the racks every 45 minutes or so, to cook the tomatoes evenly.
Cool tomatoes until they're comfortable to handle. Then fill your clean, lidded jars almost to the top and freeze.
Notes
10 pounds of tomatoes will yield about 10 cups. I filled 12 4-ounce jars and 2 16-ounce jars.