4 egg yolks
1 tbsp. + 1 tsp. lemon juice
1/4 tsp. salt
1/4 tsp. dried whole tarragon, crushed
Pinch of dry mustard
Pinch of white mustard
1/2 c. butter, melted

Combine first 7 ingredients in container of electric blender; blend on high speed 3 seconds. Turn blender to low speed; add butter to yolk mixture in a slow, steady stream. Turn blender to high speed and blend until thick. Serve over meat or vegetables. Yield: about 1 cup.