It's not easy to figure out how many calories are in a little mug of Tom & Jerry. Sure, the alcohol is a known quantity, with the couple ounces of cognac and dark rum clocking in at about 120 calories total. And the splash of hot whole milk, the only kind you want to even consider for a Tom & Jerry, is another 20. I don't think cloves, nutmeg and allspice have calories, so you don't have to worry about them. Which leaves the batter. When you take a dozen eggs, beat the whites to stiff peaks and the yolks with rum and a couple of pounds of sugar and then fold them together, that comes to a little more than 4,000 calories. But fortunately, that bowl of batter will make three- or four-dozen Tom & Jerrys, which means each drink contains a mere 250 calories or so. To put that into perspective, it's equal to a pint of real beer, and people manage to choke those down OK. The reason I've spent so much time dwelling on nutritional information is that the Tom & Jerry's perceived caloric throw-weight is the basis of the only possible objection anyone could have to it as a holiday drink. This ancient beverage—it goes back to England in the 1820s—is otherwise so delicious, so warming and so conducive to holiday cheer that, if not for the fear its ingredient list engenders, the Tom & Jerry bowl would be broken out every Thanksgiving, Christmas and New Year's by all Americans, rather than just the fearless souls in the upper Midwest. I don't know if that would bring our fractious country together, but I do know that you can have three Tom & Jerrys and still ingest fewer calories than are in a large McFlurry with M&Ms. The History and Secrets of the Tom & Jerry