Made with fresh green and yellow wax beans and a sweet and tangy vinaigrette, it's the perfect make-ahead dish for your backyard barbecue, picnic, or potluck!
Chop the green and yellow wax beans into roughly 1-inch sized pieces.Bring a large pot of lightly salted water to a boil. Boil the beans for 2 minutes until they're tender but still retain some crispness.Transfer the beans to a colander and immediately rinse with cold water until they've cooled down. Alternatively place the drained beans in a large bowl of water with ice cubes. Allow the beans to drain while you make the vinaigrette and prepare the other ingredients.
Place all of the beans in a large bowl and add the thinly sliced onion. Stir the beans and onions to combine.To prepare the vinaigrette, place all of the ingredients in a bowl and whisk until emulsified. Pour the vinaigrette over the bean salad and stir to thoroughly coat. Let the four bean salad chill for at least 2-4 hours before serving, preferably overnight.Store the bean salad in a covered, non-reactive container (such as glass) in the refrigerator where it will keep for up to 5 days.