When I first became a cooking teacher, the small school where I taught marketed the concept that paying for cooking classes would save you money in the long run. The idea was that if you were skilled enough in the culinary arts, you could walk into the kitchen, see what you had on hand and make a meal out of it, preventing an unnecessary dinner out.

Of course we all know how expensive a night out can be for a family, but there is an additional cost we all experience every time we clean out our refrigerator, and that's food waste.

The average American family wastes about 25 percent of the food and beverages they purchase. For a typical family of four that could easily add up to more than $2,000 a year. I don't know about you, but I can think of plenty of other ways to spend that money. (Right now Hawaii is sounding pretty good.)

While knowing how to cook — and more important, being willing to do it — won't eliminate all of that waste, it can significantly reduce it. For most of us, the largest amount of waste happens in the vegetable bins.

Buying lots of veggies always feels good when we're at the grocery store, but effectively planning how to use them can be a challenge. Yes, being a culinary wiz can help, but just having a few recipes in your repertoire that can accommodate several vegetable substitutions can be helpful.

Vegetable soup is the perfect example. I haven't used a recipe for vegetable soup as long as I can remember. I just open up the refrigerator, see what I have, cut it up and toss it in the pot along with some broth and whatever herbs sound good at the moment.

Stir-fries and sautés can work the same way. As long as you know which vegetables take the longest to cook, and add them first, you can use pretty much any combination.

There aren't a lot of recipes that call for winter and summer squash, for example, but having a bin full of zucchini and a butternut squash that's about to turn to the dark side calls for a bit of creativity. After all, necessity is the mother of invention, and I'm the mother of three hungry boys. Sometimes the seasons must collide in order for me to get dinner on the table.

Vegetable couscous is another recipe I turn to when I need a fast dinner and have lots of vegetables to use. In this Spiced Chicken and Vegetable Couscous, I use onion, red pepper, zucchini and cilantro. I just as easily could have used carrots, mushrooms, parsley or one of any other countless combinations.

For that matter, there's almost nothing in this recipe that can't be substituted with another ingredient. Don't have almonds? Use toasted pine nuts. No chicken? Leftover steak would be delicious. Can't find the golden raisins you thought were hiding in the back of your pantry? Chop up some dried apricots, figs or even prunes. It will all taste good.

Now that I have dinner figured out, it's time to decide how I'm going to spend that extra money. I wonder if I can find a cheap flight to Honolulu.

Meredith Deeds of Edina is the author of ­"Everyday to Entertaining" and "The Big Book of Appetizers." Reach her at meredith@­meredithdeeds.com. Follow her on Twitter: ­ @meredithdeeds.