Step 1

In a stock pot, combine the tomatoes, onions, peppers, sugar and salt; simmer, uncovered, for 45 minutes.

Step 2

Place the pickling spices, celery seed and mustard seed on a double thickness of cheesecloth; bring up the corners of the cloth and tie it with string to form a bag. Add the bag to the tomato mixture. Cook for 45 minutes or until very thick, stirring frequently.

Step 3

Add the vinegar; cook to desired thickness. Discard the spice bag. Carefully ladle the hot mixture into hot pint jars, leaving 1/2-inch headspace. Adjust the caps. Process for 15 minutes in a boiling-water canner. Editor's Tip: Water bath canning is used to preserve high acid foods, like this sauce. You can use a large stockpot if you don't have a boiling-water canner.