Choosing energy-efficient appliances when you can is the best thing you can do to create a more eco-friendly kitchen. Think about the small things, like not wasting water to rinse dishes before putting them in the dishwasher and running it only when it’s full. You also don't have to preheat your oven—simply adjust the cooking time at the end and check for doneness. And try to cook multiple dishes at once—like a roast chicken with potatoes—when possible.