417 DON'T WASTE GAS! Never light your oven to cook a single dish With a little planning you can easily prepare an entire meal while the oven is hot, as well as a pudding or tart that can be eaten cold next day. Turn out the burners directly the food is done—it will keep hot in the oven for some time. And always clean your cooker regularly—burners clogged with grease are slow and extravagant. You and your oven can do a lot to save the coal that is needed so desperately to make more guns and planes, more ships and tanks.