Sterilize Canning Jars and prep lids: You can run jars through a dishwasher cycle on high heat, or wash jars in hot soapy water, and then sterilize jars by placing them in a boiling water canner filled with water and boil for 10 minutes.Place lids (not rings) in a bowl and pour boiling water over them. Let them sit until ready to use (this softens the sealing compound).

Blanch tomatoes: Bring a large pot of water to boil.Add tomatoes and blanch for 1–2 minutes. Transfer tomatoes immediately to a bowl of ice water to cool quickly. Peel skins off with your hands or a paring knife.

Fill Jars: Chop peeled tomatoes (or leave whole/halved if you prefer) and pack them into hot, sterilized jars. Leave 1/2 inch head space at the top.For pint jars add 1 tablespoon bottled lemon juice (or 1/4 teaspoon citric acid) and 1/2 teaspoon salt. For quart jars: 2 tablespoons bottled lemon juice (or 1/2 teaspoon citric acid). and 1 teaspoon salt.

Apply lids: Run a small spatula along the inside edges of the jars to remove an air bubbles. Wipe jar rims clean, place lids on and screw bands on (not too tight).

For a Steam Canner:Add water to the base (just below the rack). Place jars on the rack (usually upto 7). Cover with the lid and heat on medium-high until a steady stream ofsteam escapes.

For a Water-Bath Canner:Place filled jars on the rack inside the canner. Cover jars with at least 1–2inches of boiling water. Cover with lid and bring back to a gentle,rolling boil. Begin timing once water is boiling.

Processing Times:Pints: 40 minutes (sea level–1,000 ft) Quarts: 45 minutes (sea level–1,000 ft)Adjust for Elevation:1,001–3,000 ft: add 5 minutes 3,001–6,000 ft: add 10 minutes 6,001–8,000 ft: add 15 minutes 8,001–10,000 ft: add 20 minutes

Remove and Rest: Carefully remove jars with a jar lifter and place on a towel-lined counter. Do not tilt jars. Let them sit undisturbed for 12–24 hours. Check seals: lids should be concave and not flex when pressed. If a jar did not seal, refrigerate it and use within a week.

Store: Label sealed jars with the date and store in a cool, dark place. Properly sealed jars of canned tomatoes will last for 12–18months (at best quality), and are often safe eating after even longer than that.