For dressing, transfer minced garlic to a small bowl. Squeeze lemon over garlic, remove any seeds and sprinkle with a pinch of salt. Allow it to rest for 10 minutes for flavors to mellow. Whisk in olive oil, and season with salt and a few grinds of black pepper. To give flavors time to develop, refrigerate for 1 hour. The dressing keeps in the refrigerator up to 3 days.
Toss chickpeas with 2 tablespoons of dressing. Refrigerate.
In a salad bowl combine cherry tomatoes and cucumber. Sprinkle with salt and pepper and toss gently with a dollop of the dressing.
Add chickpeas and sprinkle with another pinch of salt and pepper. Add an additional drizzle of dressing and toss in green onions, adding additional dressing, if necessary, to coat. Makes 4 servings.