Chicken Salad with Cooked Dressing

I love chicken salad, so I was excited to try this recipe.  It requires a double-boiler, but I don't own one, so I had to get creative.  It just so happens that my soup bowl fits over my one-quart saucepan perfectly, so voila!  I had a double-boiler.

Mix cream, chicken stock, cider vinegar, egg yolks, flour, sugar, dry mustard, salt and white pepper in double-boiler; whisk constantly over heat until mixture thickens.  Cool and then add an equal amount of mayonnaise.  Add diced chicken, and onion and celery if desired.

This was really good, but next time I make it I will add a little less vinegar because it was a tad too tangy for me.  Would be delicious as a cold meal in the summertime.