the tweetable directions:  Whisk 3 tb lemon juice, 3 yolks, S&P. Gradually whisk in 1/2 c. melted butter. Microwave 30s, whisk 30s. Rep in 10s increments until done.

A slight more involved version: http://www.epicurious.com/recipes/member/views/MICROWAVE-HOLLANDAISE-MOWBRAY-50006055