1/2 cup butter (1 stick)
4 large egg yolks
1/2 cup heavy cream (or whipping cream)
2 tablespoons lemon juice
1 teaspoon Dijon mustard
1. Cut the butter into four pieces, place in a 1-quart glass measure
or bowl, and microwave, covered with a paper towel, on high,
until almost melted, 45 seconds to 1 minute. Remove butter
from the microwave and stir until completely melted.
2. Separate eggs, placing the yolks in a small bowl and setting the
whites aside for another purpose. Beat the yolks well with a
whisk or fork, then add to the butter and stir well.
3. Add cream and lemon juice to egg mixture and stir well.
Microwave mixture, uncovered, on high, until just slightly thick,
about 1 to 2 minutes, stopping every 20 seconds to stir with a
fork. Remove sauce from microwave and stir in mustard.
4. NOTE: Sauce may be kept warm for up to 2 hours in an
insulated container. Or cool the sauce to room temperature and
refrigerate it in a covered microwave-safe container for up to 24
hours. To re-warm, cover container with plastic wrap, pierce
wrap with a knife to vent, and microwave on 50 percent power
until heated through, about 3 to 4 minutes, stopping to stir
halfway through. Do not allow sauce to boil.