Heat half the olive oil in a large casserole dish. Brown the lamb and chicken on all sides and season with salt and pepper. Remove the chicken and set aside. Add the onions and tomatoes and simmer 10 minutes.
Add 3 litres water and bring to the boil. Reduce heat and simmer 1 hour.
Add the turnips, celery, paprika, coriander and cumin. Return the chicken to the casserole and simmer another 50 minutes. Add the pumpkin and carrots and simmer another 20 minutes.
Add the zucchini and chickpeas and simmer 20 minutes. Add water if necessary.
Prepare the couscous according to packet instructions. Fry the sausages in a fry pan. Arrange the meat and vegetables on a platter with the couscous.