In a medium saucepan, bring water, 2 teaspoons olive oil, and garlic to a boil. Stir in the couscous. Cover tightly and remove from heat. Leave covered for 5 minutes to steam until all water is absorbed. Use a fork to fluff and break up any lumps.
Heat a skillet over medium-low heat, spray with grape seed oil. Add drained chickpeas and spices: cumin, coriander, ginger, and cinnamon. Stir for few minutes until all spices are aromatic and chickpeas are coated with the toasted spices. Remove from heat.
Transfer prepared couscous to a large serving bowl. Mix in tomatoes, green onions, and chickpeas. Add lemon juice, remaining olive oil, basil, and salt and pepper to taste. Refrigerate 30 minutes before serving.