Homemade Canned Tomato Sauce

Start by filling a large container with water and placing it on the stovetop to reach boiling point. Next, prepare an ice-filled container for cooling down the tomatoes immediately after blanching.

Now, place the tomatoes into the boiling water in batches and let them cook for 30 to 45 seconds. Remove them from the boiling water and quickly transfer them into the ice-filled container to stop the cooking process. Remove the skin from each tomato and cut it in half. Use your fingers or a spoon to remove the seeds.

In a separate pan, heat some olive oil over medium heat and add sliced onions. Cook the onions until they become translucent, stirring occasionally, which should take around 5 minutes.

Now, combine the cooked tomatoes with the onions, lemon juice, red wine, minced garlic, chopped celery, fresh basil leaves, diced red sweet pepper, salt, bay leaves, and ground black pepper in a large saucepan over medium heat. Stir everything together until the tomatoes have broken down and the sauce has thickened, which should take around 10 minutes.

Prepare your canning equipment by submerging the jars and lids in boiling water for at least 5 minutes to sterilize them. Fill each hot, sterilized jar with the tomato sauce and leave about 1/4 inch of space at the top. Close the jars with clean lids and screw on the rings.

Fill a large container, specifically designed for canning, with water according to its manufacturer's instructions. Bring the water to a boil and carefully place the jars into it using a holder. If necessary, add more boiling water to ensure that the water level is at least 1 inch above the tops of the jars. Process the jars in the canner for 35 minutes, which is equivalent to 8 pints.

Once you've removed the jars from the canner, place them on a cloth-covered or wood surface, several inches apart, and let them cool completely over the course of 8 hours to overnight. To check if the jars are sealed properly, press on the top of each lid gently with your finger. If the lid doesn't move up or down at all, it's a good sign that the seal is tight. Finally, store the sealed jars in a cool, dark area.