How Dental Floss Cut the Perfect Birthday Cake Slices

A single strand of Johnson & Johnson unflavored dental floss ran straight through a triple-layer red velvet cake at Lila’s bakery in Brooklyn, October 14, 2018. No serrated knife, no crumbs stuck to the blade, and every slice landed picture-perfect on the plate-even the thick cream cheese frosting didn’t drag or collapse. Lila swears by unwaxed floss and stretches it tight above the cake before pressing it down in one smooth motion, then pulls it out cleanly from the side. Each cut stays sharp, and she wipes off the floss with a damp cloth between each pass. The real secret is the floss’s super thin nylon edge-it’s taut enough to glide through any cake, even chilled cheesecake, without a single smudge. And that October day, she cut twenty-four flawless slices in under four minutes, all thanks to a two-dollar box of dental floss.