To cook smart, use as much of each food item as you can. There’s no question of throwing away egg whites, the last of that leftover wine in the bottle or stale bread; they are still perfect for preparing a variety of meals. Here are five everyday foods and ways to use them to their full potential.

1. Egg yolks and whites

Some recipes only call for the egg white or yolk. Although making an omelette is an option, there are also several other uses for these leftovers.

Egg whites are known to bring lightness to dishes once they are whipped. Use the whites in a waffle batter to make them soft or stir them vigorously to create a foam that will garnish cocktails. Egg whites are also the basic ingredient for meringues.

As for egg yolks, their fat content gives richness to a dish. It can be used to prepare a homemade Caesar vinaigrette or a famous crème brûlée. Egg yolks can also be frozen. Simply stir them and pour them into an ice cube tray, covering them with a drop of oil so the cold doesn’t dry them out.

2. Wine

Is there some leftover wine in the bottle from last weekend? It certainly won’t end up in the sink. Whether it’s white or red, it can enhance the taste of many dishes. You can make a marinade, use it as a base for braising meat or fish, to deglaze a pan or to make a sauce. It is also possible to freeze the wine in an ice cube tray for later use.

3. Stale bread

Is last night’s baguette hard as a rock this morning? It’s possible to revive it! Simply quickly rinse the bread under water and put it in the oven at 400°F for 10 minutes to restore its crispy texture. Dry bread is also ideal for making croutons for a salad or cheese fondue, for cooking a strata for brunch and for preparing breadcrumbs.

4. Parmesan crust

Yes! Even your Parmesan rind won’t find the way to compost so easily as it’s packed with potential. Since it’s too hard to eat as is, use it to flavour soups, broths and sauces, where you simply drop it in and leave it to simmer. Just don’t forget to remove it from your dish before serving.

5. Buttermilk

Buttermilk is one of those ingredients that is often only needed in a very small amount in a recipe, which means there’s always plenty left over. One option is to freeze it for future use, but you can also use it in your pizza dough by replacing the water with the same amount of buttermilk, which will give it a soft and elastic texture. It can also replace milk or cream in mashed potatoes and tenderizes meat when it’s added to a marinade.