The first thing to say about popovers is that they don't actually pop over. They pop up.
This was not always obvious to me. I will admit to actually standing by the oven window the first time I made them (this was very long ago and very far away), waiting for the little nubbins to do somersaults right there in their pans. When they didn't, I thought I had failed.
So call them popovers but think of them as pop-ups.
The next thing to say about popovers is that they are ridiculously easy to make. They are made from a batter consisting basically of eggs, milk and flour. Proportions are a cup of flour and a cup of milk to every two eggs. This will make six or eight good-sized popovers.
When they come out of the oven, popovers look like puffy, browned chefs' hats -- they are more or less straight on the sides and billowy at the top where no container has restrained them. And though they may collapse a bit as they cool, particularly if they are on the underdone side, they stay impressive-looking throughout the meal.
To make a popover to suit your meal, you can enrich the basic mixture with a tablespoon or so of melted butter, flavor it with salt, herbs, cheese, bits of ham, or sweeten it with sugar. If you substitute whole-wheat flour for half of the total quantity of flour, you have added a very nutritious little punch to your meal.
The fact that popovers puff up so spectacularly is due partly to their composition, but mostly to the vessels they are baked in.
Popover batter is basically identical to crepe batter. Both batters are thin -- about the consistency of heavy cream -- and both are just mixed, not beaten, so as not to excite the gluten in the flour. But crepes are cooked in as thin a layer as possible so that no air pockets are allowed to develop. Their beauty is in their thinness.
Popovers, on the other hand, should look as voluptuous and puffy and possible. Baked in vessels ideally taller than they are wide, in the end popovers are nothing but a thin layer of cooked batter surrounding a great deal of air. The air gets incorporated thanks to steam that's produced when the very liquid batter meets the hot oven. Voila , a big poof.
Popovers -- being traditionally an American invention in contrast to the French crepes and British Yorkshire pudding, which is again from essentially the same batter -- have traditionally been baked in heavy cast-iron pans. Popover pans look like muffin pans except that the cups are deeper.
But in the last few years there has been some competition for the traditional cast iron. Several companies now make individual heavy-gauge aluminum pans with nice little lips so that during the final poof in the oven, the popover would have something to support its billowy top. These pans come singly, or they come as a group of six, all attached to each other by way of an aluminum rod.
And, truthfully, you could probably find something in your kitchen to make popovers in even if you didn't have a special pan. Deep custard cups will do, as will individual souffle' dishes or tinned steel dariole molds. The dariole molds, used for making individual-sized hot or cold molded dishes, are ideal, being quite tall.
In trying all the different pans, I've found that it actually doesn't make much difference to the quality of the popovers which you use. For the sheer impressiveness of final results, the highest pan is the best.
Cast iron looks down-home and American, but it's devilishly heavy. It holds heat better than aluminum or steel and seems to produce a faster puff, but not an appreciable difference in final volume. The advantage cast iron pans do have is that you can make more in one batch -- there are 11 cups in each pan.
And they come in two cup sizes, one of which is quite small and dainty. The aluminum pans on the other hand are generously sized, and make quite a definitive popover statement.
Most popover recipes call for the pans to be preheated, which is more crucial with a material like cast iron that is so slow to heat up (then so slow to give up its heat).
Although it's disillusioning to know that there is not -- so far, at least -- a batter that will actually turn itself over in the oven, there is some consolation in knowing that popovers, unlike their trickier relatives, the souffle's and the cakes, will always pop up.