1. Heat oil in saucepan over medium heat. Add onion, and cook until soft, stirring often (5-8 minutes). Stir in garlic, cumin, coriander, ginger, and cinnamon and cook until fragrant (30 seconds).
2. Stir in tomatoes, chickpeas, and water. Simmer until liquid thickens (10 minutes).
3. While tagine simmers, cook couscous according to package instructions.
4. Stir dates and lemon juice into thickened tagine. Serve over couscous, sprinkled with cilantro.