Memorize this and you'll be set in the kitchen.
The Internet abounds with tips and tricks for minimizing food waste, but few are as succinct as the advice given by Love Food, Hate Waste Canada (LFHW) on its website: Plan It. Use It. Eat It. I like this line because it's catchy, easy to remember, and therefore easier to implement.
PLAN IT focuses on the importance of having a meal plan of sorts, even a rough one. Some people like to plan out the entire week in advance, while others do it the day of. I make a point of thinking about dinner first thing in the morning, just so I can remember to start soaking beans or take food out of the freezer to thaw. This gives me a chance to think about what needs to get eaten, i.e. a head of lettuce that's going limp or some tofu past its expiry date. LFHW suggests scheduling a lazy night with no plan. This way, you don't buy groceries you don't need or that won't keep, and can instead eat out with friends, get takeout, or polish off leftovers.USE IT provides information on how to care for ingredients. Whether it's learning to interpret expiry dates, how to use a freezer effectively, how to make stock from vegetable and meat scraps, or learning to can/preserve, dehydrate, or revive limp foods, there are countless ways to breathe new life into sad, forgotten ingredients. It also has a section on how to keep ingredients fresh, to prevent future losses.
EAT IT has a long list of delicious recipes, many of which feature leftover ingredients – for example, Fridge Harvest Frittata or Stew, Leftover Mashed Potato Gnocchi, Cookie Crumbs Pie Crust, pesto (a great way to use many kinds of leftover greens), etc. The more you cook, the more comfortable you'll become with incorporating random extra ingredients into other dishes, for the sole purpose of using them up. I did this the other night, making a delicious chickpea curry with leftover onions, a huge bag of limp spinach, a half can of coconut milk, and some tomatoes.
Love Food, Hate Waste is a great resource for anyone wanting to cut back on waste in the kitchen. Check it out here. LFHW was also involved in the creation of this great new free cookbook, 'Rock What You've Got,' available for download as a PDF.