Years ago, I was at a friend’s house and I wanted to make some chocolate chip cookies. When I went digging in her pantry, I found baking powder that had expired many, many years earlier. I tossed it, ...

If your favorite baking recipes suddenly stop turning out well, don’t panic! There may be a simple answer—your leavener may be expired. (By the way, this is the difference between baking soda and ...