We’ve all experienced the annoying phenomenon of having the first batch of pancakes turn out splotched with brown spots, while subsequent batches come out evenly golden. Here’s why: When fresh oil hits a hot pan, the surface tension of the oil causes it to bead together into little droplets, leaving some of the pan bottom without a coating. Since bare metal conducts heat better than oil, when you ladle your batter into the pan, the spots directly in contact with uncoated metal will cook faster than those touching oil. By the time you get to your second batch of pancakes, the oil has undergone chemical changes that make the molecules less prone to clustering. What’s more, the first batch of pancakes has absorbed much of the oil, leaving only a thin film that’s more likely to be evenly distributed across the pan.
For spot-free pancakes from the get-go, start by applying oil to an unheated pan or griddle. Allow the oil to heat up over medium heat for at least one minute, then use a paper towel to wipe away all but a thin, barely visible layer to prevent sticking. The pancakes should cook up golden brown from the first batch to the last.