In general, I don’t think I’m very good at making desserts. I have had many disasters with oven temperatures that cause burned cookies, tough cupcakes, liquid-y banana bread, and more. Fortunately, most things turn out well enough when enough sugar is added, and because I’m usually willing to stomach my own mistakes, food usually gets eaten.
Although I may not have the precision and conscientiousness necessary for baking, I still appreciate the magic that it sometimes yields. This past weekend, I happened to try a lemon pudding cake recipe, mostly because I had a lemon picked off a tree and a new carton of eggs. If you’re not already familiar with it, I would like you to take a minute to consider this recipe: it requires 4 separated eggs, and the baking dish is half-submerged in a water bath in the oven. What do you think will happen?
If you’re scientifically-naive like me, you might think that you’ll end up with a wonderfully fluffy and moist cake. The eggs will probably be whipped up a lot, and the water will create a steamy oven for the cake. Unfortunately, that was wrong, but fortunately, the result was far cooler. Forgive me for cheating on the writer’s directive to “show, don’t tell”:
Note the 2 distinct layers of the cake: the bottom of the pan is still delicious lemon pudding while the top has developed into a fluffy lemon cake. While Julie, Joe, and I were eating it, we discussed the secret of the cake, which actually wasn’t very tricky at all.
Although the water bath did generate a lot of steam, that wasn’t the point: instead, it kept the bottom of the pan closer to the boiling point of water (212 degrees F) while the rest of the oven, including the pan and cake above the water, at 350 degrees. One of the few facts I remember from high school chemistry is that water will remain at the same temperature until it completes a state change. In this case, the water, although in a very hot oven, will stay at 212F until it turns into steam. It’s left as an exercise for the reader to determine how long it would take for the steam to reach 350F.
So the bottom stays cooler than the top, and apparently, the transition between pudding and cake is between those temperatures. Also interesting is that the cake and pudding happen to have the same recipe and just need to be cooked differently. If you look at a recipe for lemon pudding and angel food cake (a close relative being another meringue-based cake), they’re not so different. The cornstarch in the pudding is substituted with flour to thicken the pudding, and the cake has milk over water and the egg yolks mixed into the batter as well. Amazing.
One final fun thought about this dessert. It turns out that the pan I was using was a little small, and the batter came right up to the top. Without a leavening agent like baking soda or baking powder, I figured it would be okay, since the cake wouldn’t rise and overflow the pan. I was half-right about that.
In the picture, you can see that the cake is below the rim, but when I pulled the cake out, it was well-above the rim, but the cake still had the perfectly rectangular shape from the pan. Apparently, the cake had set before spilling over, but it wasn’t really rising: instead, I think the pudding and perhaps air in the cake itself had expanded from the heat and pushed the cake up before settling back down after cooling.
Anyways, I hope you’re as amused at this cake as I was, and I hope you make it sometime sooner to enjoy it as much as I did. In the meantime, I expect the high school science teachers out there to be using the lemon pudding cake in homework questions. Science is all around us.