In a large bowl, add chopped kale and a tablespoon of lemon juice. Squeeze or massage kale with your hand for about 2-3 minutes. This will tenderize the kale. Set aside.
Slice or cut the red onion, cucumber, red bell pepper and zucchini. Add to the bowl with the kale.
Add grape tomatoes, Kalamata olives and feta to the mixture.
Mix lemon juice and olive oil. Pour mixture into salad.