This recipe was clipped from packaging of some kind, likely a Heinz product since its vinegar is one of the ingredients required. Date unknown. Recipe is typed below along with a scanned copy.

Zucchini Pickles

4 cups Heinz Apple Cider Flavored Vinegar
2 cups granulated sugar
1/4 cup salt
2 teaspoons celery seed
2 teaspoons ground turmeric
1 teaspoon dry mustard
5 pounds (5 to 6-inch) zucchini, unpeeled, cut into 1/4-inch slices
1 quart thinly sliced onions (4-5 medium)

Combine first 6 ingredients in saucepan; bring to a boil. Pour over zucchini and onions; let stand 1 hour, stirring occasionally. In saucepot, bring mixture to a boil, then simmer 3 minutes. Continue simmering while quickly packing one clean, hot jar at a time. Fill to within 1/2 inch of top making sure vinegar solution covers vegetables. Cap each jar at once. Process 5 minutes in boiling-water bath. Makes 6-7 pints.

Before using this recipe, it’s important to read this page, the “Safe Canning & Food Preservation” section.