What do paint and mayonnaise have in common? Preferably not much, except both are emulsions -- combinations of two liquids that do not mix. I can't imagine life without the common emulsions used in cooking: milk, cream, butter, and especially mayonnaise. Real mayonnaise, not Miracle Whip, has always been de rigueur at our house and I've gone back to making my own ever since I paid a recent visit to the port of Mahon on the Mediterranean island of Minorca, where mayonnaise originated. Mayonnaise