For an easy yet flavorful roast leg of lamb, start by preheating your oven to 350°F (175°C). Rub the lamb leg with a mixture of minced garlic, chopped rosemary, olive oil, salt, and pepper, ensuring it's evenly coated. Place the seasoned lamb leg in a roasting pan and add a splash of water or broth to the bottom of the pan to keep it moist. Optionally, you can add vegetables like potatoes, carrots, and onions around the lamb for a complete meal. Once done, let the lamb rest for 10-15 minutes before slicing and serving with your favorite sides. Enjoy your delicious and easy-to-make roast leg of lamb!