Turns out some so-called tricks for boiling pasta and cleaning your favorite pan don't really work so well after all. There are a number or tried and tested methods that do.
Add oil to pasta water to prevent noodles from sticking: We have all seen the instructions on the back of the fresh-pasta package: Add a spoonful of oil to the cooking water to keep your fettuccine from turning into a big blob. But turns out that is just a waste of oil. Salt the water — which doesn't have anything to do with sticking; it just seasons the pasta — stir every few minutes while the noodles cook, and once you have drained them, toss with a tablespoon of olive oil to keep them separated.
Replace baking powder every six months: Leavening agents like baking powder do have a shelf life — old ingredients are often the reason for flat baked goods — but don't automatically assume a canister is useless if it is past the six-month mark. You can test yours by sprinkling a spoonful into a cup of warm water; if it makes the water effervescent, it is fine to use.
Let hot food cool completely before refrigerating it: It is true that putting a big pot of piping hot soup directly into the fridge isn't ideal as it makes the motor work harder, but the other extreme—letting that minestrone sit out until it is cold and then packing it up for storage—isn't great, either because microorganisms that could lead to foodborne illness tend to multiply in conditions between 40 degrees and 140 degrees. It is better to transfer the hot soup to smaller containers, which will help it cool more quickly than it would in the pot. They can sit on the counter, uncovered, for two hours. Then, snap on the lids and refrigerate.
Don't use soap on cast iron: Although cast-iron pans look tough, they can be high maintenance: The conventional wisdom is to avoid washing them with soap, not to put them in the dishwasher and not to let them air dry — use a towel or they will rust. Those last two rules are important to follow. If a pan is well seasoned, it is fine to wash it in cold water or with a little bit of soap. The oil you used to season the pan should prevent the cleaner from penetrating too deeply. Use kosher salt to scrub off sticky residue, then re-season the pan by heating it in a warm oven and rubbing it with oil.