Finishing a dish with browned butter — or beurre noisette if you’re French — is an easy way to add a little bit of impressive luxury. Once you know how to do it, it almost feels like cheating. Simmer some butter over low heat until the solids fall out, then keep cooking until they turn a deep, golden brown. Spoon the nutty, rich sauce over vegetables, carbs, or anything else you desire to make it taste like it came from a fancy French bistro.
Should you brown salted or unsalted butter?
You can brown both salted and unsalted butter, but most recipes call for unsalted. There are two reasons. One is that the amount of salt in salted butter varies from brand to brand, and a lot of cookbook authors and chefs like the control that comes with browning unsalted butter, then salting to taste as needed. Clarifying the butter also removes some of the salt. According to Cook’s Illustrated, the salt gets coated in browned milk solids, “adding bulk but not flavour.”
The second reason you may want to use unsalted butter is that it’s easier to gauge and harder to burn. When added to an aqueous solution (like the water boiling off of your butter), salt increases the surface tension of the water, making the bubbles stronger. This creates a thicker, more stable foam, and all that extra foaming makes it hard to detect more nuanced colour changes. This can lead to the butter burning instead of browning, which will taste bitter and acrid instead of nutty and delicious.
Don’t panic if you want to brown butter and only have the salted stuff available, but pay close attention as it browns, and use a spoon to move the foam as needed so you can notice those colour changes the moment they happen. (And even if you do accidentally burn it, don’t toss it out. It has several other tasty uses.)