Beat up two eggs with two tablespoonfuls of sugar, add a piece of butter the size of half an egg, a teaspoonful of mustard, a little pepper, and lastly a teacup of vinegar. Put all of these ingredients into a dish over the fire and cook like a soft CUSTARD. Some think it improved by adding half a cupful of thick sweet CREAM to this Dressing; in that case use less vinegar. Either way is very fine.
The Whitehouse Cookbook, by Mrs. F.L. Gillette (Year 1887)