Here’s what I’ve learned from many late-night baking disasters: substitution is more art than science. If you swap salted for unsalted, and the result is 10% saltier than perfect, you still made something edible. The world won’t end. Your friends will still eat it. But if you’re baking for a competition or a very picky grandmother (like mine), just buy the unsalted butter.
In the meantime? Keep a stick of salted butter in the fridge, and a stick of unsalted in the freezer. Be prepared. And if all else fails, add a tiny pinch of sugar to your dough to balance the extra salt—that’s my secret. Now go bake something delicious, and don’t let a little sodium ruin your night.