Sous Vide Hollandaise

Using sous vide circulator, bring water to 167°F/75°C in 7-quart container. In small saucepan, combine vinegar and shallot and bring to boil over high heat. Cook until vinegar is reduced by half, about 1 minute. Strain mixture through fine-mesh strainer set over small bowl, pressing on shallots to extract as much liquid as possible. Discard shallots.

Combine vinegar reduction, butter, egg yolks, water, lemon juice, and salt in 1-quart zipper-lock freezer bag. Seal bag, pressing out as much air as possible. Gently lower bag into prepared water bath until mixture is fully submerged, and then clip top corner of bag to side of water bath container, allowing remaining air bubbles to rise to top of bag. Reopen 1 corner of zipper, release remaining air bubbles, and reseal bag. Cover and cook for at least 12 minutes or up to 30 minutes.

Transfer mixture to blender and process until smooth, about 1 minute, scraping down sides of blender jar as needed. Serve immediately.