I posted a full review of our recent trip to Brennan's restaurant here in New Orleans to rec. Food. Restaurants, and thought I'd share the recipes here.
Melt the butter in a medium saucepan; skim and discard the milk solids from the top of the butter. Hold the clarified butter over very low heat while preparing the egg yolks. Place the egg yolks, vinegar, cayenne, and salt in a large stainless steel bowl and whisk briefly. Fill a saucepan or Dutch oven large enough to accomodate the bowl with about 1 inch of water. Heat the water to just below the boiling point. Set the bowl in the pan over the water; do not let the water touch the bottom of the bowl. Whisk the egg yolk mixture until slightly thickened, then drizzle the clarified butter into the yolks, whisking constantly. If the bottom of the bowl becomes hotter than warm to the touch, remove the bowl from the pan for a few seconds to cool. When all of the butter is incorporated and the sauce is thick, beat in the water. Serve immediately or keep in a warm place at room temperature until use. Yields 2 cups.