Bearnaise sauce

Heat the butter in a medium saucepan over medium heat just to melt.

Boil shallots, tarragon, and peppercorns in vinegar and wine in a nonreactive medium-size saucepan over medium heat until reduced to about 1/4 cup. Strain into the top of a double boiler. Whisk in the egg yolks

Place the top over the bottom of the double boiler containing simmering water. Make sure that the top of the water is below the bottom of the upper part of the double boiler. Whisk constantly

The second that the yolk mixture begins to thicken slightly, remove the top of the double boiler from above the hot water and continue whisking. Turn off the heat

Add four ice cubes to the bottom of the double boiler to cool the hot water a little. Put the pan of yolks back above the hot water. Whisk in the melted butter, drizzling it in very slowly. If at any time the sauce looks as if it is about to break, remove the top and continue whisking to cool it down or whisk in 1 teaspoon cold water

With constant whisking, whisk in the salt and cayenne. When all the butter is incorporated, taste and add more salt or cayenne as needed.