So you undertake the decidedly oldschool but comforting job of making a pudding. You carefully stir the beaten eggs into the hot milk mixture, but soon you see the dreaded signs of mixture separation. And when it breaks, it breaks fast—and now you’ve got a watery pile of scrambled eggs suspended in a milky broth. The problem is a failure to temper, the critical heat-control technique that basically acclimates eggs to higher heat.The solution: Slowly whisk a thin stream of the hot milk mixture into beaten raw eggs in a bowl. Tempering will heat the eggs gradually without cooking them completely. The milk-egg mixture can then be returned to the pan and cooked as the recipe requires. Be patient cooking, though: If you crank up the heat after tempering, you can still wreck things, even with the inclusion of flour or cornstarch helping to stabilize. A small jump in the pudding’s temperature can lead to coagulation.