Three Bean Salad is a timeless American picnic and potluck staple, prized for its tangy-sweet dressing and vibrant trio of beans. It's known for its ease of preparation and long shelf life, often getting better after a day or two as the flavors meld. This version includes a crunchy mix of bell peppers and onions, with a sweet-tart marinade that infuses every bite. Great for summer gatherings or as a make-ahead side dish.