In a medium microwaveable bowl, melt the butter completely.
Whisk in the lemon juice and then the eggs yolks one at a time.
Microwave in 30 second increments, whisking well after each 30 seconds. After 2 30-second bursts, add the water and cayenne pepper.
Microwave for two more 30-second bursts. The hollandaise should be thick enough for the whisk to leave marks in the sauce. Adjust the salt to taste.
