Soak the Red Onions: Soak the chopped onions in ice cold water for approximately 10 minutes, drain, and set aside. This helps reduce the bitterness of the onions.
Combine All Ingredients: In a large bowl, combine all of the ingredients and stir to combine. Taste and adjust the seasoning with more lemon, sugar, salt and pepper. Cover the salad tightly with plastic wrap, or transfer to an airtight container, and place it in the refrigerator for at least an hour.
Serve & Enjoy: When you are ready to serve the chickpea salad, toss to combine and adjust seasoning as necessary. The salad can be made two days in advance.