At Christmas Eve dinner last December, my 14-year-old niece, Ava, asked me to show her how to make the blender hollandaise sauce my mother introduced to our repertoire more than 40 years ago. In the seconds it took for the hot melted butter to combine with the whirring egg yolks and lemon juice, a tradition had passed to the next generation.

I didn't dwell on the moment; the hollandaise was getting cold. Not a good thing for a warm butter sauce.

Hollandaise is a special treat to be enjoyed the moment it is ready. To those of you who know only the sad imitations that top Sunday brunch eggs Benedict in restaurants, I offer this advice: Learn how to make it at home.

During my career as a professional chef, I prepared hundreds of gallons of sauce the "restaurant" way. I dumped the yolk mixture into a giant stainless steel bowl, whisked it into fluff over a direct flame, beat in clarified butter and served it to the masses.

I owe the masses an apology. Time constraints in restaurant kitchens make it all but impossible to consistently serve this sauce at its peak.

By way of atoning, I have spent weeks experimenting with three methods simple enough for any home cook: by blender, by microwave and by hand. I can see the e-mails already: The fat! The eggs! But the fact is, hollandaise is worthy of an occasional guilt-free indulgence. As a condiment, not a beverage.

"It's a very fine sauce," says Yannick Cam, chef-owner of downtown Washington's Le Paradou. "It can be contemporary. With blood orange in it, it's fabulous, especially on poached turbot. It has its place, but people associate it with classical cuisine."

In other words, people assume it's too heavy to even consider. It's not diet food, but a tablespoon of hollandaise usually contains about 70 calories and 7 grams of fat, while a tablespoon of that lime-ginger compound butter melting on your simple piece of grilled salmon clocks in at about 100 calories and 11 grams of fat.

That's because there's more to hollandaise than flavored butter.

One of the "mother" sauces in classical French cuisine, hollandaise is an emulsion, a combination of two liquids that normally would repel each other (in this case, butter and lemon juice), aided by an emulsifier (egg yolks). The cold version is mayonnaise.

What makes hollandaise particularly refined is that it is the least stable, and therefore most delicate, of the mother sauces. The egg yolks are capable of absorbing only so much butter, while the lemon juice helps buffer them from the heat.

The trick is to heat the yolks enough (between 160 and 165 degrees) for them to take in the butter and stabilize in a creamy state of suspension but stop short of the point (180 degrees) where they curdle into an awful mess.

Those temperatures also kill salmonella; to be safe, the finished sauce should be kept at 140 degrees or higher until served.

Chef-author Madeleine Kamman quite admirably explains the whole process, and most every other cooking process, in "The New Making of a Cook" (William Morrow and Co., 1997). But I was after something simpler.

Of the three methods I worked with, the microwave one, adapted from a recipe by chef Michel Richard, results in the most stable sauce, because Richard uses cornstarch as an extra thickening agent.

The blender and microwave versions are easier, replacing the heat of the stove with preheated butter, microwaves and the whir of machines. The classic method requires more attention and skill, and the opportunities for error are more abundant, but the texture is silken.

Four decades ago, my mother's blender version was used to adorn creamed or wilted spinach nestled in artichoke bottoms, a supremely simple dish that has reappeared at every family feast since.

Whichever version you make and however you use it, remember that hollandaise is best prepared at the last minute, eaten while still warm, and discarded when left over. Reheating is not impossible, but it's tricky, and quality suffers greatly. Besides, if you had some today, you certainly don't need any tomorrow.

David Hagedorn is a professional chef and former restaurateur.