Ingredients
6 medium white onions, sliced
4 quarts zucchini, sliced
1 green pepper, sliced
1 red pepper, sliced
1/3 C. salt
2 trays ice cubes, or equivalent
3 C. white vinegar
4 c. sugar
1 1/2 tsp. turmeric
1 1/2 tsp. celery seed
2 Tbsp. mustard seed

Procedure
Slice onions, zucchini and peppers. Layer with salt and ice cubes in large stock pot, ending with ice cubes. Let stand three hours, adding more ice part-way through if most of the initial ice seems to have melted.

Meanwhile, wash 8 pint-size canning jars. About 20 minutes before the end of the three-hour sitting time for the vegetables, place the jars on a cookie sheet and place in cool oven. Turn oven on to 250 degrees. Remove from oven when ready to ladle pickles into them.

Boil canning jar lids.

Drain ice water from vegetables. Combine vinegar, sugar, turmeric, celery seed and mustard seed. Pour mixture over sliced vegetables. Heat just to boiling.

Fill hot jars with hot pickles and brine. Put on hot lids.

Pasteurize them in a 180-degree water bath for 30  minutes

Makes 8 pints.
Creative Canning Cuisine website