An egg white is 87% water. That's a lot. So when I see recipes that use only egg yolks and then add additional water or perhaps liquid dairy, I quickly began making rough calculated adjustments. Today we were playing with the lemon custard from our friend Stella's book. She uses yolks and then adds water. I treated whites as pure water and adjusted her recipe to accommodate my changes. The custard cooked up beautifully and no whites were wasted. (In her recipe she uses her whites for the meringue in her lemon meringue pie. I did not need to make meringue. I needed a decadent lemon pie filling.)
Next time you contemplate making a custard try using the whole egg.
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