Preheat the oven to 400 degrees. Place the red pepper, onion, zucchini, chickpeas and preserved lemon on a baking sheet, drizzle with olive oil and mix to coat all the veggies.
Combine the chicken broth, orange juice, butter, salt, cumin, paprika, ginger and allspice in a large saucepan and heat to boiling. Add the couscous, bring back to a simmer, turn down the heat and cover.