You wouldn't flush your hard-earned money down the drain, so why let last night's leftovers go to waste? Our collection of ideas and recipes will help you creatively -- and deliciously -- reinvent your food. 

When there's just a tiny bit of mustard left in the jar, don't throw it out. Instead, toss in a few ingredients, and shake a tangy Dijon vinaigrette right in the container.

Leftover, cold mashed spuds might as well be labeled, "Now what?" But these tasty recipes for using them up may even convince you to make extra.

Mashed-Potato Pancakes
Potato Croquettes
Potato-Leek Soup

Next time you bake a cake, don't toss the trimmings into the trash without a second thought. Instead, keep them to use as building blocks for another dessert. We saved chocolate cake scraps and layered them with whipped cream and fresh raspberries for a quick and easy trifle. Freeze cake morsels in an airtight container for up to one month.

Use up leftover rice, plus whatever vegetables and protein you have on hand, in a delicious one-dish meal.

Quesadillas are a delicious way to use leftover cooked meat. Keep tortillas, cheese, and jarred salsa on hand. Sandwich the ingredients between the tortillas, and cook in a skillet with a bit of oil for a few minutes per side.

The Cuban sandwich -- the classic combination of roast pork, ham, and cheese -- was once the province of humble Cuban coffee shops. Now high-end chefs are getting into the act. Create your own homemade version with leftover ham.

Turn leftover chicken or turkey bones into a flavorful stock to use in future meals.

Don't let an abundance of herbs go to waste. Pluck several types of sprigs -- we chose basil, mint, and thyme -- and use them to flavor a basic sugar syrup. Mix the concoction with ice and sparkling water, then garnish the drinks with additional sprigs. You can also freeze the infused syrup in ice cube trays and enjoy it for up to a month.

Don't pour leftover wine from your dinner party down the drain! Instead, pour the remainder into a resealable bag and freeze it. Next time you need to deglaze a pan after frying or sauteeing meat, just add a 1/2 cup of your reserved wine and a bit of butter.

Turn your leftover roasted chicken into a Mexican-flavored soup for a light supper.

The scraps of dough that get left behind when a pie heads for the oven can be turned into delectable little treats.

Frittatas are a common way to use up leftover vegetables, but did you know you can use the same technique with leftover pasta and sauce for a more substantial dinner?

Create a delicious spread with any combo of hard cheeses (for tang) and soft cheeses (for texture) lying around in your fridge. We mixed 1 ounce each of manchego, Parmesan, and Roquefort (use at room temperature, and cut hard kinds into small pieces), 3 ounces goat cheese, 2 tablespoons heavy cream, and 1 teaspoon grappa (optional), and pulsed the mixture in a food processor for about 15 seconds, until combined but chunky.

The next time you have leftover bread from a meal, make homemade breadcrumbs -- you'll save a few dollars without skimping on flavor. Tossed with lemon zest, herbs, and Parmesan cheese, these fresh breadcrumbs are perfect for coating chicken, pork, or turkey cutlets, or as a pasta topping.

Pesto is a great way to use up any remaining herbs and nuts. Adjust the quantity of the ingredients depending on what you have, the flavors you like, and the number you're serving.

Over the years, hash has become a catchall term for almost any combination of chopped ingredients whose diverse flavors come together amiably in a skillet. It is the perfect way to use up leftover meat and potatoes.

An easy way to finish off leftover meat and vegetables is to make pasta.

Salmon Pasta with Spicy Tomato Sauce
Linguine with Beef and Onions
Pasta with Ham and Mushrooms

Reinvent leftover chicken into a satisfying salad by adding some greens, vegetables, and your favorite dressing.

After using fresh herbs, save and freeze stems in a resealable bag. Before you zest a lemon, peel off a few strips and freeze them as well. If a recipe calls for ginger, save some of that peel, too. Throw all of these leftover ingredients in a pot of boiling water, and voila -- you've created a flavorful broth in which to poach fish.