1. Bring a large saucepan of water to the boil. Add asparagus and simmer for 2 minutes or until just tender, drain.
2. Combine egg yolks, lemon juice, orange juice and orange rind in a blender or food processor, blend for 10 seconds.
3. Melt butter in a small saucepan until bubbling, immediately pour into food processor or blender, while motor is operating, in a slow steady stream. Place asparagus on a serving plate, spoon sauce over the top and garnish with strips of orange rind.