No-Fail Popovers | Cook's Illustrated (2024)

Imade a lot of popovers when Iwas in high school, which might give you the impression that Iwas a very sophisticated teen. Iwasn’t. Imade them because the recipe was easy and required only inexpensive pantry ingredients, which made popovers a perfect after-school snack for my siblings and me. Imixed together milk, eggs, flour, and salt; poured the mixture into the wells of a preheated, greased muffin tin (we didn’t have a specialized popover pan); and baked them in a hot oven, turning down the temperature halfway through baking to prevent the outsides from burning while the insides finished cooking. When all went well, the cups of batter ballooned dramatically into crisp, hollow shells with creamy, custardy interior walls, and Ifelt like Ihad invented fire.

But it didn’t always go well, even though Ialways used the same recipe. About 25 percent of the time my popovers were squat and spongy, like damp, bland muffins. Other times I’d lift seemingly perfect popovers out of the tin only to reveal bases that were comically shrunken. (We ate all these imperfect specimens; we were teenagers.) Over the years, Igrew exasperated with my frequent inexplicable failures, so Istopped making popovers. But now that developing foolproof recipes is my job, Ifelt ready to confront the challenge anew. I’d figure out what makes popovers pop (or not pop), and I’d test all aspects of their production to find a formula and baking method that guaranteed success every time.

There’s not much written about what makes popovers pop, but our science research editor, Paul Adams, confirmed my suspicion that the science is similar to that of pitas and cream puffs: The oven’s heat rapidly gels the surface of the batter so that when the moisture inside turns to steam and expands, that surface is able to stretch to retain it, leaving a growing hollow inside. Eventually the exterior dries out so much that the protein in the eggs and flour forms a rigid shell, halting expansion. The inner walls, protected from the fiercest heat, remain moist. Equipped with this new insight, Ihit the kitchen and made fivepopover recipes that varied in their choice of flour, choice of milk, number of eggs, mixing methods, and baking temperatures.

With my new understanding of popover mechanics, Isuspected that the extra gluten-forming protein in bread flour would make the batter even stretchier and thus produce loftier popovers. It did. Not only were popovers made with bread flour about 30 percent taller than those made with all-purpose flour, but their higher walls were also thinner, making them a bit more crisp, and that crispness held up as they cooled. Bread flour was in. Next up: the milk.

Even if they achieve an impressive height, popovers are often marred by bases that look comically small in relation to their expansive tops. See “Elements of a Perfect Popover” for the simple steps that we took to prevent this common flaw in our recipe.

In the test kitchen, whole milk is our default, but, wondering if low-fat or even skim milk might be better, Imade threebatches of popovers, each with milk of a different fat level. There wasn’t a huge difference in stature, but Idid notice a slight difference in texture: The lower the proportion of milk fat, the crisper the popover. Skim milk made slightly more crisp popovers, and those made with whole milk were a bit softer. But the differences were so slight that Iwent with low-fat milk because that’s what many cooks are likely to have on hand. And besides, the next ingredient under consideration—butter—had a bigger impact. Though many recipes call for adding melted butter to the batter, Ifound it to have an even greater softening effect than higher-fat milk. I’d omit the butter completely and save it for spreading on my baked popover, where Icould really appreciate it.

But about those popover-pan cups: Should they be hot? Should they be greased? My standard high school MO was to combine both of these: Heat the pan with a bit of fat in each cup and then pour in the batter. This method yielded popovers that were light, expanded, and crisp, but it also yielded the greatest number of shrunken bases. The heat from the pan seemed to jump-start the rise, but that hot fat prevented the batter from gaining purchase on the sides of the cups. Adding cold batter to cold, very lightly greased cups ensured just enough grip for the popovers to have full, round bases, but overall they weren’t as tall.

Early heat clearly helped the rise, but maybe that heat could come from the batter instead of the pan. In fact, maybe that was the principle behind recipes that called for room-temperature milk and eggs, whose popovers tended to rise higher than those made with cold ingredients. But Iwas reluctant to have to think that far ahead when Imade popovers. My solution: use fridge-cold eggs, but warm the milk to 120degrees in the microwave. This warm batter made towering popovers. Now to refine the baking method.