WRITTEN BY Lesley Holland Downey Concealer is at the heart of my holy grail hunt for perfection—and it’s what I get the most questions about. After all, the right concealer can make you look more well-rested, hide a blemish, even your skin tone and add brightness to your face. Concealer, according to Bobbi Brown, is “the secret to the universe,” and I fully subscribe to that philosophy, but with some caveats. You must choose carefully based on what you are using it for, how you are applying it …