To make the dressing, squeeze the juice from 1 lemon into a bowl. Add 3 tablespoons of extra virgin olive oil, 2 minced garlic cloves, ½ teaspoon of salt, ¼ teaspoon of freshly ground black pepper.
In a large salad bowl, add the beans, bell pepper, onions and parsley, and stir. Add the feta cheese and stir gently and toss to combine.