Prepare canner, mason jars for canning, and lids.

Wash and sort tomatoes, removing any bruised or discolored product.

Quarter 6 tomatoes and place in a large stainless steel sauce saucepan. Bring to a boil over medium-high heat. Using a potato masher, crush tomatoes to release juices, stirring constantly.

While maintaining a boil and stirring to prevent burning, quarter additional tomatoes, adding them to the saucepan as you work. Make sure the mixture continues to boil vigorously while you add, stir and crush the remaining canning tomatoes. When all tomatoes have been added, boil, stirring occasionally, until tomatoes are soft and juicy, about 10 minutes. Remove from heat.

Working in batches, press tomatoes through a fine sieve, food mill or Victorio strainer to remove skins and seeds. Discard skins and seeds.

Return mixture to saucepan and bring to a boil over high heat, stirring frequently. Reduce heat to medium-high and boil until volume is reduced by at least one-third for a thin sauce. For a thicker sauce, cook until reduced by half.

Before filing each jar with tomato sauce, add lemon juice or citric acid to the hot jar in the quantity specified below:

Pint: ¼ tsp Citric Acid or 1 Tbsp bottled lemon juice

Quart: ½ tsp Citric Acid or 2 Tbsp bottled lemon juice

Add salt (optional) in the quantity specified below:

Pint: ½ tsp

Quart: 1 tsp

Add dried herbs (optional) to each jar.

Ladle hot sauce into prepared jars, leaving ½ inch headspace. Remove air bubbles and adjust headspace, if necessary, by adding hot sauce. Wipe rim. Center lid on jar. Screw band down until resistance is met, then increase to fingertip-tight.

Place jars in canner, ensuring they are completely covered with water. Bring to a boil and process pint jars for 35 minutes and quart jars for 40 minutes, adjusting for altitude. Remove canner lid. Wait 5 minutes, then remove jars, cool and store. For each quart jar of thin sauce, you'll need about 5 lbs of tomatoes.