Also called Zabaione or Zabaglione to the Italians, who claim they invented it. I call it Lemon Curd.

Sabayon

1/2 C granulated sugar
3 egg yolks – cream together eggs and sugar in a double boiler
Add 1/2 tsp vanilla or 1/2 vanilla bean – seeds removed – beans into sugar
Add 2 TBL dry white wine plus 1/2 tsp vinegar.
Continue to whisk until mixture starts to thicken. (8-15 minutes)
Take on and off as require to keep at a low temperature
Watch out for eggs cooking against the sides of the bowl.
This is your sabayon. Set aside for later use.

Creme Fraiche Custard

Make creme fraiche.
Mix 1/2 C cold creme fraiche and 1/2 C cold heavy whipping cream.
Beat in Kitchen Aid until it doubles or even triples in size.
Fold together whipped creams and sabayon.
Put into serving dishes and top with blueberries, peaches, plumbs or nectarines – in winter use pears or soaked dried frigs, apricots, strawberry, blueberry, grapes, prunes, etc

This must be made at the last minute, and served immediately, or it deflates and separates and becomes watery.

Serving idea: Serve in same sized bowls, but each one a different shape. Goodwill is a good source for this hodgepodge of serving dishes.

To create a Sabayon Topping

Pick your liquid: Can be practically anything based on what you are trying to accomplish. White wine, chicken stock, grapefruit juice, coffee, ginger ale, etc.
Measure your ingredients: Generally the ratio is 1:1:1 egg yolk, sugar, liquid – figure one egg per person
Mis-en-place: which means have everything ready. This will need to be constantly whisked, so you don’t have time to measure ingredients as you go.
You will be whisking over a double boiler. I always just make my own. This is how. You should NEVER let your water get to a full rolling boil. Always just a simmer.
Cream together egg yolk and sugar, when the color changes, drizzle in your liquid and start cooking over your double boiler. Move the mixing bowl on and off the heat as needed.

Here are flavor combinations from Food52.com to try:

Savory:

Sweet: