Step 1 In a heavy stockpot, heat the butter with the oil over medium heat and saute the onions, stirring, for 5 minutes.
Step 2 Add the chicken and the veal or lamb and cook, turning the meats, until they are opaque, about 5 minutes per side.
Step 3Add the water, tomatoes, ginger, cinnamon sticks, paprika, cayenne, saffron, the bag of parsley and cilantro, salt and pepper. Bring to a boil, skim off the foam, cover and simmer over low heat until the chicken is tender, 45 to 50 minutes. With a slotted spoon, remove the chicken to a bowl so it doesn't overcook. Cover and keep warm.
Step 4Continue cooking the broth until the veal or lamb is tender, about 1 hour longer. (While the meat is cooking, start preparing the couscous.) Remove the meat.
Step 5Add the carrots, turnips and celery to the broth. Raise the heat until it comes to a simmer, then lower the heat and cook for 15 minutes.
Step 6Add the zucchini, squash and chickpeas; raise the heat again until the liquid returns to a simmer. Lower the heat and cook until the vegetables are tender but not mushy, about 20 minutes more. As vegetables are done, remove them to a bowl.
Step 7Return the chicken and meat to the pot until warmed through and adjust seasonings to taste. Discard the cheesecloth bag. (The broth and vegetables can be prepared a day ahead.)
Step 8If necessary, reheat the broth, meats and vegetables. Mound the steamed couscous on a large platter. Make a big well in the middle and pile some of the vegetables into it. Arrange the meat and chicken around the couscous and scatter chickpeas around it. Moisten with about 1 cup of the broth. If you like, mix 1 cup broth with 1 1/2 to 2 tablespoons harissa to serve on the side. Serve the rest of the vegetables and broth in a large, deep bowl, accompanied by the harissa.