Melt the butter on the stove until it reaches 200°. Don't let it get any hotter or it will burn the milk solids
Add the rest of the ingredients to a blender and blend on high for 5 seconds until combined
with the blender running, SLOWLY stream in the butter until the entire batch is emulsified. If you add the butter too quickly, the emulsion will break and the sauce will be ruined
Serve warm