Moroccan Lamb with Couscous

• 1 cup vegetable stock
• 1 cup couscous
• 2 tbsp extra virgin olive oil
• 2 tbsp Moroccan seasoning
• 350 g lamb backstrap
• 2 tomatoes, roughly chopped
• 0.5 red onion, diced
• 400 g chickpeas, drained and rinsed
• 0.5 cup fresh coriander (cilantro) leaves, roughly chopped
• 100 g baby spinach, shredded
• 1 lemon, cut into wedges
• 200 g tzatziki