I consider Shepherd's Pie to be pretty close to a complete meal. Tons of protein from the meat, veggies, a little savory saltiness with the parmesan cheese.... It's easy to make and can be made a few days in advance and kept refrigerated until baking. Adding mushrooms gives more flavor (and of course more nutrition - they are very good for you!) and using chicken stock in the potatoes and "gravy" helps to keep everything moist. I love it!