This traditional sauce shared by our test kitchen adds an elegant touch to fresh steamed asparagus. The rich lemony mixture is the typical sauce for eggs Benedict and is also delicious served over broccoli.

Editor's Note: To make a double boiler, place a stainless steel mixing bowl in a saucepan. The bowl should partially fit (not completely fit) into the saucepan. Fill the saucepan with enough water so that when the bowl rests in the saucepan the water does not touch the bottom of the bowl. Bring the water to a simmer. Add the ingredients to the bowl and place the bowl in the saucepan.