Wash your tomatoes well then remove the stems and any bruised parts.

Decide how you are going to remove the stems and seeds. Either blanch to remove the skins before cooking, freeze and thaw to remove the skins, use a blender to puree or process through a food mill after cooking the tomatoes a little.

Place skinned and seeded or pureed tomatoes into a heavy stockpot.

Bring to a boil over medium heat, then turn down to simmer. Let the sauce simmer until it's as thick as you like your tomato sauce to be. Reduce by 1/4 for thin sauce or 1/2 for a thick sauce.

When your sauce has cooked down and is as thick as you like add salt to taste.

Ladle into canning jars. Add 2 TBS. of lemon juice per quart jar, and 1 TBS per pint jar to raise the acidity level.

Release any air bubbles by running a plastic spatula around the inside edge of the jars.

Wipe the rims clean and add the lids and rings finger tight.

Place the jars into your water bath canner and process pints for 35 minutes and quart jars for 40 minutes, adjust the time to your altitude.