Place the onions in a bowl of cool water and let them soak while you prepare the other ingredients (this removes the harsher bite from the onions, while still giving great flavor).
Place the chickpeas, parsley, bell peppers, cucumber, and feta in a large serving bowl.
In a small mixing bowl or large measuring cup, stir together the dressing ingredients: olive oil, red wine vinegar, garlic, oregano, salt and pepper. Drain the red onions and add them to the chickpea mixture, then pour the dressing over the top. Toss to combine. If time allows, let marinate in the refrigerator for 30 minutes, or enjoy immediately.
Store leftovers in the refrigerator for up to 3 days.
Serving ideas: This salad is lovely as is, but to transform it into a main dish, try it stuffed inside pita pockets with hummus and mashed avocado or add grilled chicken and serve it over salad greens with an extra squire of lemon juice and drizzle of olive oil.