Loosen the frozen tomatoes

• Run warm water over the frozen tomatoes to break them apart from the solid block.
• Transfer them to the large stockpot.

Cook the tomatoes down

• Cook the tomatoes on the stove over a gentle heat until completely broken down and reduced.

Blend the sauce

• Blend the cooked tomatoes with an immersion blender until smooth.

Strain out seeds and skins

• Pass the blended sauce through a fine sieve into a smaller pot, pressing with a ladle.
• Discard the seeds and skin left in the sieve.

Simmer with seasoning

• Return the strained sauce to the stove and stir in the Italian-style spaghetti seasoning.
• Simmer gently until thickened to a sauce consistency.

Prepare the jars

• Wash the jars thoroughly, even if they look clean.
• Rinse them in cool water with a splash of vinegar.

Add citric acid and fill

• Put a quarter teaspoon of citric acid into each jar.
• Fill the jars with the hot sauce, leaving headspace.

Seal the jars

• Wipe the rims clean.
• Close with lids and rings, finger tight.

Water bath can

• Load the jars into the water bath canner with a splash of vinegar in the water.
• Bring to a rolling boil and process.