Preheat the oven to 400° F.
In a large bowl, toss the chicken with olive oil, brown sugar, spices and 1 tsp kosher salt until well-coated. Let marinate for 10 minutes while you prepare the other ingredients.
Heat a large skillet, preferably cast-iron, over medium heat. Sear the chicken thighs for 3-4 minutes per side or until browned. It’s OK if they are not fully cooked yet. Transfer to a plate and set aside, leaving at least 1 tbsp of rendered fat in the skillet.
Add the shallot, carrot and garlic to the skillet. Sauté for 2-3 minutes, until the shallots begin to soften. Add the chickpeas, couscous, dates and chicken stock. Bring to a boil over high heat and nestle in the seared chicken thighs, pouring over any juices left on the plate. Arrange the lemon slices on top.
Transfer the skillet to the oven and bake for 15 minutes or until the chicken is cooked through and the couscous is al dente. Let rest for 10 minutes before serving with fresh herbs.