Comfort foods are traditionally fattening fare, but you can slim down your shepherd's pie with a few tweaks.

Created in northern England and Scotland, where sheep herding was big, shepherd’s pie evolved from classic meat pie dishes made in the Middle Ages. Today, this stick-to-your-ribs meal is an American favorite.

A great way to use leftovers, shepherd’s pie is a combination of minced meat (usually lamb or mutton) with gravy and veggies, finished with a mashed potato topping. Another variation -- called "cottage pie" -- uses beef. Whichever filling you use, most recipes call for the addition of fat, fat and more fat! And, well, that doesn't make for a healthy eat. In fact, traditional recipes have more than 1,000 calories and 60 grams of fat per serving.

If you want to stick to the classic preparation, lighten up the meat portion by using a 90% or higher ground sirloin beef. Ground turkey, ground venison and ground bison are all low-fat alternatives. For a vegetarian pie, try texturized vegetable protein (a.k.a. TVP or "fake" ground beef) that, believe it or not, tastes quite yummy. TVP is versatile and works well alone or mixed with other meats because it picks up the flavor of whatever you mix it with. Other filler options include chopped portobello mushrooms, eggplant or beans.

Carrots, onions, corn and peas are typical shepherd’s pie add-ins. Experiment with different vegetables such as cauliflower or mushrooms. Frozen mixed veggies are a good time-saver. Try making a veggie-filled pie with scrumptious winter produce such as parsnips, rutabaga, roasted garlic and Swiss chard.

These days shepherd’s pie is a good dish for Thanksgiving leftovers, but sweet potatoes and turkey are a winning combination any time of year. You can make your mashed potato topping with conventional russet potatoes, but try Yukon gold, sweet potato or a combination. If you opt for sweet potatoes, mash a banana into them as your very own "secret ingredient."

When I worked at a culinary school, all I heard was "fat equals flavor." This is true. Thing is, too much fat also equals a quadruple bypass. The mashed potatoes and gravy are where the fat is. Slim down high-fat ingredients such as half-and-half, butter, oil and heavy cream by using lower-fat substitutes such as regular or low-fat milk or light cream.

Ellie Krieger's Shepherd's Pie: this Healthy Eats-approved dish weighs in at only 340 calories and 9 grams of fat.

Or use the suggestions above to lighten up Rachael Ray's 30-Minute Shepherd's Pie.