Peel and dice the cucumber into 1/2-inch pieces, dice the tomatoes into similar-sized chunks, finely dice the onion, and chop the fresh parsley. I always chop my parsley right before using it to preserve its bright aroma—it really makes a difference in the final salad. Drain and rinse the canned chickpeas under cold water to remove excess sodium and starch.
In a small bowl or cup, whisk together the olive oil, lemon juice, pressed garlic, Italian seasoning, and red pepper flakes until well combined. The acid and oil will begin to emulsify slightly, creating a cohesive dressing. I recommend pressing your garlic rather than mincing it—it distributes more evenly throughout the dressing and prevents any harsh garlic pieces in individual bites.
Combine the prepared chickpeas, cucumber, tomatoes, onion, and parsley in a large bowl. Pour the dressing from Step 2 over the vegetables and chickpeas, then toss everything together until evenly coated. Season with salt and black pepper to taste, tossing again to distribute the seasonings evenly.