Bring a large pot of water to a boil. Add green beans and cook for 5 minutes or until just tender.
While the green beans are cooking, prepare a large bowl of ice water. Remove green beans from pot with a spider strainer or large slotted spoon and place directly into the ice water to stop the cooking process. Drain and pat dry.
In a small bowl, soak red onions in cold water for 5 minutes to reduce pungency. Drain and pat dry.
In large bowl, combine blanched green beans, red kidney beans, garbanzo beans, red onion and celery.
In a mason jar, combine white wine vinegar, extra virgin olive oil, garlic, Dijon mustard, dried oregano and honey. Tightly secure lid and shake until emulsified. Season with salt and pepper to taste and shake again.
Pour the vinaigrette into the bowl of beans along with fresh parsley. Gently toss to evenly distribute. Season with salt and pepper to taste.
Refrigerate at least 1 hour prior to serving.