Grilled Lamb Skewers with Couscous Tabbouleh

Name: Grilled Lamb Skewers with Couscous Tabbouleh
Ingredients: 1 10 oz. box couscous; 1 1/2 c. plain low-fat yogurt; 1 tbsp. plus 1 tsp. cumin; 2 garlic cloves, minced; Juice of 2 lemons; kosher salt; Freshly ground black pepper; 1 1/2 lb. leg of lamb, cut into 1 1/2 in. chunks; 2 tomatoes, seeded and diced; 1/2 English cucumber, halved, seeded, and diced; 1/2 small red onion, finely chopped; 1/4 c. Finely chopped fresh parsley; 1/4 c. finely chopped fresh mint; 3 tbsp. extra-virgin olive oil; Lemon wedges, for serving