Blanch and peel tomatoes
Chop tomatoes into desired size
Add lemon juice to each canning jar
Add chopped tomatoes
Pour boiling water over tomatoes. Fill just to where the rings on the jar begin making certain you leave at least ½ inch head space. Remove air bubbles by running a plastic knife around inside of jar and tapping bottom jar gently against counter.
Wipe rim of jars clean and add lid and band
Place jar in a water bath canning pot half filled with warm water. Add additional water level covers the top of the jars by 1-2 inches.
Cover pot and bring to a roiling boil. Once boiling, lower temperature so there is a gentle but steady boil. Boil quarts for 45 minutes and pints for 40 minutes. (Adjust time for altitude - see below)
Remove jars from canner and place on a towel or a baking rack to cool. Do not touch jars or tighten lids until at least 12 hours.
After jars have cooled, check lids for a proper seal by pressing on the center of each lid. The lids should not have any give in the center. Remove bands wipe down jars to remove any residue. Label and store in a cool, dark place.