In a small bowl, whisk together the extra virgin olive oil, lemon juice, minced garlic, dried oregano, sea salt, and black pepper to create the dressing.
Place the chicken breast in a shallow dish and coat with half of the prepared dressing; let marinate for 10 minutes.
Preheat a grill or grill pan over medium-high heat and cook the chicken for 5-6 minutes per side until fully cooked and juices run clear.
While the chicken cooks, rinse and drain the chickpeas, halve the cherry tomatoes, dice the cucumber, and finely chop the red onion and parsley.
In a large bowl, combine the chickpeas, tomatoes, cucumber, and onion.
Slice the grilled chicken into strips and add it to the bowl.
Drizzle the remaining dressing over the bowl, garnish with fresh parsley, and toss gently before serving.