This is a favorite of my family.
Combine kidney beans, onion, hard-boiled eggs, pickles, mayonnaise, and celery in a large bowl until well combined. Season with salt and black pepper.
Refrigerate 8 hours to overnight to allow flavors to combine.
Per Serving: 399 calories; protein 7.9g; carbohydrates 22.8g; fat 31.4g; cholesterol 84.6mg; sodium 565.7mg.