• Step 1: In a large mixing bowl, combine the drained and rinsed kidney beans, garbanzo beans, green beans, and wax beans.
• Step 2: Add the diced red onion to the bean mixture.
• Step 3: In a separate small bowl, whisk together the apple cider vinegar, olive oil, white sugar, salt, and black pepper to create the dressing.
• Step 4: Pour the dressing over the bean mixture and stir to coat evenly.
• Step 5: Cover the bowl and refrigerate the four bean salad for at least 30 minutes to allow the flavors to meld.
• Step 6: Taste and adjust seasoning as needed before serving chilled or at room temperature.