Start by rinsing the beans under cold water, and make sure to drain them well. This helps remove any canning liquid that might overwhelm the fresh flavors. Chop your celery, finely mince the soaked onion, and rough-chop the parsley and diced bell peppers. The goal here is to create bite-sized pieces that all come together beautifully.

In a large mixing bowl, carefully toss together the three types of beans, celery, onion, parsley, rosemary, and bell pepper. Give it a gentle stir to ensure everything is well combined without smashing those beans!

In a separate small bowl, whisk together the apple cider vinegar, granulated sugar, olive oil, salt, and pepper. It might take a minute to dissolve the sugar completely. Just keep whisking until you have a smooth mixture.

Pour the dressing over the bean mixture. Using a spatula or a large spoon, toss everything together until the beans and veggies are well coated in that delicious dressing. This step is vital because it allows all those flavors to mingle!

Transfer the salad to the refrigerator and let it chill for at least an hour. If you can wait even longer—up to several hours—do it! As the salad sits, the beans absorb the flavors of the dressing, making each bite even more delightful. Just before serving, let it sit at room temperature for about 15 minutes to bring it back to the right temperature for eating.