Zippy 'maters ( Tomatoes )

Got this from Southern Living.

• Ready In: 2 hrs 20 mins
• Yields: 8 cups

Ingredients

• 5  large tomatoes
• 1⁄4 cup  thinly sliced onion
• 1⁄2 cup cider vinegar
• 2  tablespoons sugar
• 1  tablespoon olive oil
• 1⁄2 teaspoon celery seed
• 1⁄4 teaspoon salt
• 1⁄4 teaspoon pepper

Directions

1. Cut tomatoes into chunks.
2. Stir together tomato and remaining ingredients; cover and chill 2 hours.