Preheat your oven to 400°F (200°C). On a baking sheet, toss sliced zucchini with olive oil, salt, and pepper. Spread them out evenly and roast in the preheated oven for about 20 minutes, or until tender and slightly golden.

In a medium saucepan, bring the vegetable broth to a boil. Stir in the couscous, cover, and remove from heat. Let it sit for about 5 minutes, then fluff with a fork.

In a small bowl, combine the harissa paste, smoked paprika, and a pinch of salt and pepper. Mix well to create a glaze.

Heat a skillet over medium heat and add a drizzle of olive oil. Season the salmon fillets with salt and pepper. Place them skin-side down in the skillet and cook for about 4-5 minutes, until the skin is crispy. Flip the salmon and brush the harissa glaze generously on top. Cook for an additional 3-4 minutes or until the salmon is cooked through and flakes easily with a fork.

In a bowl, combine Greek yogurt, minced garlic, lemon juice, chopped dill, salt, and pepper. Mix well and adjust seasoning to taste.

On a plate, serve a portion of fluffy couscous topped with roasted zucchini. Place a salmon fillet on top and drizzle with extra harissa glaze if desired. Add a generous dollop of tzatziki on the side and garnish with fresh mint leaves.