Peel and chop the carrots, turnips, celery, zucchini, and bell peppers.

In a large pot, heat olive oil over medium heat and add the chicken thighs and lamb pieces.

Add sliced onion to the pot and cook until soft.

Stir in prepared vegetables, tomato concentrate, canned tomatoes, chickpeas, saffron, and spices. Add water to cover.

Cover and simmer on low for about 50 minutes.

Cook the merguez sausages separately until browned.

Prepare couscous as per package instructions.

Plate couscous, top with meats and vegetables, and serve with harissa.