Make the glaze: Whisk together 2 tablespoons harissa paste, 2 tablespoons honey, 2 tablespoons olive oil, 2 tablespoons lemon juice, 3 garlic cloves, minced, 1 teaspoons cumin, 1 teaspoons smoked paprika, 0.5 teaspoons salt, and 0.3 teaspoons black pepper in a bowl.
Marinate the chicken: Pound 4 boneless skinless chicken breasts to an even thickness (about ¾ inch). Coat them in half the harissa-honey mixture, reserving the rest. Let sit while you prep the couscous, or up to 30 minutes.
Cook the couscous: Bring 1.5 cups chicken broth and 1 tablespoons olive oil (for couscous) to a boil. Stir in 1.5 cups couscous, cover, and remove from heat. Let steam for 5 minutes.
Sear the chicken: Heat a skillet over medium-high heat with a drizzle of oil. Cook the chicken for 5–6 minutes per side until golden and cooked through (165°F internal). In the last minute, spoon the reserved glaze over the top and let it caramelize.
Fluff and finish couscous: Fluff 1.5 cups couscous with a fork. Fold in 0.3 cups fresh parsley, chopped, 0.3 cups fresh mint, chopped, and the zest from 1 lemon, zested and cut into wedges.
Serve: Slice chicken and serve over the herbed couscous with lemon wedges on the side. Drizzle any pan juices over the top.