The Tom and Jerry comes to us from Jerry Thomas, author of the first real cocktail book, The Bartenders Guide - How To Mix Drinks or The Bon Vivant's Companion. The book dates back to 1862, so this drink is about 150 years old. This is a wonderful drink that is well worth the effort necessary to make it.
Stir the batter before you prepare each drink, as the sugar will quickly go to the bottom. Also, I use VS Cognac instead of brandy in mine.
You can make a batch of the batter and freeze it in canning jars. Thaw a jar in cold water. Put on a pot of hot water, break out the brandy and rum, and you'll soon be sipping a Tom and Jerry without having to make a mess with the beater.
Be careful when adding the hot water. You want the rum and brandy to already be mixed with the batter before you pour in the hot water. The liquor insulates the batter from the shock of the hot water. If the hot water hits the batter directly, it can curdle (or cook) the eggs, and you'll have little curdled egg bits in your drink.
Jerry Thomas's recipe calls for a larger batch of batter:
5 lbs sugar
2 oz Jamaica rum
1 1/2 teaspoons ground cinnamon
1/2 teaspoon ground cloves
1/2 teaspoon ground allspice
Jerry uses a wineglass of brandy (or half brandy and half rum) in a Tom and Jerry. That is 4 oz of booze. I have cut this to 2 oz, but if you want the real thing, use 4 oz. They knew how to drink back then.
Here are some other notes from his book:
"Adepts at the bar, in serving Tom and Jerry, sometimes adopt a mixture of 1/2 brandy, 1/4 Jamaica rum, and 1/4 Santa Cruz rum, instead of brandy plain. This compound is usually mixed and kept in a bottle, and a wine-glassful is used to each tumbler of Tom and Jerry.
"A tea-spoonful of cream of tartar, or about as much carbonate of soda as you can get on a dime, will prevent the sugar from settling to the bottom of the mixture.
"This drink is sometimes called Copenhagen, and sometimes Jerry Thomas."