Americans waste a lot of food. Every year, we throw away approximately 30 million tons of food. Don't worry (or do!), we're not alone; apparently those goody-goody Swedes throw away roughly a quarter of the food that they buy. Sure, we might be composting like crazy these days, but still, when you think about it, throwing away that much food is still a waste of money. (See also: 10 Ways to Cut Waste When Feeding Kids)

My grandmother, who spent a better part of her childhood in Nazi prison camps, instilled in her children a strong conviction that wasting food was downright sinful. I've never gotten over that lesson, so I live in a rather paranoid world where refusing to take home your leftovers from a night of Chinese food is almost on par with punching a kitten: It's just not done. I have become rather adept at using up leftovers. The food that I find myself wasting these days turns out to be stuff that I never previously thought of as food, per se.

This past summer, I was meandering through a local farmers market when I came across a stall manned by a Hmong farmer and his wife. On display he had dozens of different vegetables that I had never seen before. Something I was rather surprised to see included was the leftover greenery from the harvest of summer squash. I asked the gentleman who was bagging up my purchase about the squash stems and leaves. Having recently had a terrible experience with undercooked taro leaves, I was leery of anything new and exciting, and the greenery of most gourds is covered in tiny thorns that scratch the skin — not exactly something that I was eager to ingest.

Seeing my apprehension, the farmer laughed and said, "These are scratchy, but not if you cook them for loooong time, like we do." Intrigued, I looked up recipes for squash leaves online later that day, and found that squash greens are used in laksa, a noodle soup common in Southeast Asia. I had happily eaten squash blossoms before, but never the greens.

Intrigued, I started thinking about other greens from our gardens and refrigerators that we throw away once the harvest is over.

Carrot Greens

Carrot tops can be boiled for soup stock, along with things like celery and fennel bottoms, fennel fronds, woody herb stems, and the rinds of hard cheese, bones, and apple cores. You still end up throwing away the leftover bits, but at least you're getting all the flavor out first. If you're feeling more adventurous, you can use carrot greens in a way akin to parsley.

Cauliflower Leaves

These are often removed from a head of cauliflower before you buy, but if they are still attached, you can cook them with the cauliflower. They're just like cabbage.

Broccoli and Cauliflower Stems

This might seem like a no-brainer, but lots of people discard the stems from broccoli and cauliflower. Just thinly slice the stems and cook with the rest of your veggies. Stems contain fiber and nutrients, too.

Radish Greens

The tops of a bunch of red radishes or daikon are a spicy treat. Because they are often sandy, I triple wash mine before cooking.

Pea Greens

Anyone from China can tell you that dou miao are a delicacy. Sauteed with garlic and sesame oil, pea greens are healthy and delicious.

Watermelon Rinds

You probably already know that you can pickle watermelon rind, but you can also simply cook with it — it acts very much like the Chinese winter melon that is so popular in soups. Watermelonrind.com has a big list of rind recipes that you can print out (staring at that web site might cause severe eye strain). Try to ignore all of the brand name recommendations; you can use any brand of cumin that you want when making watermelon rind curry.

Potato Skins

I'm honestly baffled by anyone who would peel a potato and not eat the skin; the flavor and texture of potato skins is my favorite part of a French fry. But if you're a mashed potato purist, keep the clean potato skins to the side and fry them up as a crunchy topping for meats or salads.

Squash Seeds

Also big in China, salted watermelon and pumpkin seeds are a delicious snack. Although many roasted pumpkin seed recipes call for an oven temp of 325°F, you can also cook the seeds at 250°F over a longer period. Try seasoning with kosher salt and spicy Indian masalas, like Kitchen King, before roasting.

Garlic and Onion Tops and Flowers

You'd have to be living under a rock not to know how useful garlic scapes are in cooking. While it's true that most grocery stores carry only the bulbs, if you grow your own garlic and onions or buy yours from a local farmer's market, you can take advantage of the whole plant.

Banana Peels

Yes, you can eat banana peels. If chopped finely, they add a distinct (if unfamiliar) flavor to savory dishes, including this Indian curry dish, and this recipe, which combines banana peels with black eyed peas. One enterprising chef and writer even made banana peel cakes. Banana peels can also be used, like many fruit peels, to create homemade vinegar.

Coffee and Coffee Grounds

Used coffee grounds are great in the garden as slug deterrent, but leftover coffee is also a meat tenderizer. Leftover coffee grounds can also be used in recipes that call for a lot of chocolate, like cake or homemade truffles.

Tomato Greens

Gardeners are often loath to part with the fragrant tomato greens. I've always been told to avoid tomato greens due to toxic chemicals contained therein. Well, it turns out that their toxic reputation* may not be so deserved, because tomato greens are in use at Chez Panisse and other establishments, and have been since 1987 (see page 2 for citation).

* While no conclusive data has shown tomato greens to be particularly toxic, you should exercise restraint when eating any plant that you haven't previously consumed. Tomatine, the toxin that exists in tomato vines and green tomatoes, both of which are technically edible, is dangerous in large doses. So don't go eating a pound of tomato vines.

Animal Parts

Most of us don't deal in whole hunks of animals, but who hasn't stared down a sack of giblets at Thanksgiving and wondered why turkey hearts were so unappetizing? I'm not fond of kidneys, myself, but I have a newfound appreciation for deep-fried gizzards. Liver and marrow make meat and tomato sauces more rich, thick, and satisfying.

Are there fruit and vegetable parts that you have found a use for? How about unusual cuts of meat?