Cool to room temperature. Return to bowl; add corn, celery and garlic powder. Whisk olive oil and vinegar in a bowl; drizzle over potatoes and onions; toss to coat well. Season with salt and pepper.
Apple cider vinegar has long had a reputation as an elixir ... It’s usually made by fermenting corn, wheat, potatoes, grapes and a variety of other plants through a two-step process.