Beurre blanc

Beurre blanc (French pronunciation: [bœʁ blɑ̃]; "white butter" in French) or Beurre Nantais (French pronunciation: [bœʁ nɑ̃tɛ]) is a warm emulsified butter sauce made with a reduction of vinegar and/or white wine (normally Muscadet) and shallots into which softened whole butter is whisked in off the heat to prevent separation. The small amount of emulsifiers naturally found in butter, including a trace of lecithin,^[1] is used to form an oil-in-water emulsion. Although similar to hollandaise in concept, it is considered neither a classic leading nor compound sauce.^[2] This sauce originates in the cuisine of the Loire-Atlantique department.