Heat the oil in a saucepan over high heat and cook the lamb and chicken for 5 minutes or until brown.
Add the onions and garlic to the saucepan and cook for several more minutes or until golden brown.
Add the tomatoes, chicken stock, ras el hanout, cumin, coriander, sage and paprika. Season with salt and pepper. Simmer for 10 minutes.
Add the turnips, carrots, zucchinis and parsley then simmer for 1 hour. Stir in the chickpeas and cook for 10 minutes.
Prepare the couscous according to manufacturer's directions. Add the butter to the grains and mix well with a fork, separating the grains to prevent lumps from forming.
Take 2 or 3 ladles of stock from the saucepan and pour into a bowl then add the harissa to the stock. Mix well.
Serve the spicy stock in the bowl along with the beef and lamb stew and couscous.
Ras el hanout
Ras el hanout is a blend of spices from North Africa. There is not a permanent combination of spices that are used, each maker has their own secret combination often containing over a dozen spices, sometimes as many as a hundred. Typically they would include cardamom, clove, cinnamon, chilli powder, coriander, cumin, nutmeg, peppercorn and turmeric. If you cannot find this blend make your own by using the above mentioned ingredients or use a curry powder.