Step 1Combine lemon juice and harissa in a large bowl. Add lamb; toss to coat. Set aside to marinate for 10 minutes.
Step 2Spray a large heavy-based frying pan with oil; set over medium-high heat. Add lamb and harissa mix; cook, tossing, until lamb is evenly browned. Transfer the lamb and pan juices to a plate, and set aside.
Step 3Return pan to heat; spray again with olive oil. Add onions, carrots, parsnips and garlic; cook, stirring often, for 4–5 minutes, or until vegetables are heated through. Add tomatoes, stock, and lamb and pan juices; cover and bring to the boil. Reduce heat; cover and simmer, stirring occasionally, for 25–30 minutes, or until vegies are tender. Season with cracked black pepper.
Step 4Stir through spinach and scatter with coriander. Serve stew with warmed pita breads, yoghurt and lemon wedges.