Passover Sponge Cake with Potato Starch

An identified modern formula

The recipe follows the potato-starch Passover sponge from Spice and Spirit, as excerpted by Chabad. Seven eggs are separated and one more is kept whole. The whole egg belongs with the yolks; the seven whites are beaten with the sugar before the mixtures are folded together.

That extra whole egg is easy to overlook in a shopping list. There are eight eggs in total, rather than seven eggs with an instruction to return one of their whites to the yolks. Keeping the two lines separate makes the preparation easier to follow.

Older Jewish cookbooks also adapt egg-risen cakes for Passover. The 1897 Economical Jewish Cook gives a Swiss-roll variation using potato flour or motza meal. This tube cake takes a different shape, with the central tube supporting the sponge from within.

Hold the air gently

Start with clean bowls and beaters, and keep yolk out of the bowl of whites. The whites should become glossy and hold a firm peak. Dry clumps are harder to fold through without leaving streaks or knocking out too much air.

The starch is sifted to break up lumps, then folded into the eggs a little at a time. This is a different action from beating a butter cake after every addition. Work around the bowl and underneath the mixture until combined, then stop and fill the prepared pan.

The pan is part of the method

A smooth aluminum tube pan with a removable base gives support around both the outside and center. Its ungreased surface is deliberate. A decorative nonstick Bundt pan has a different coating and shape, so it isn't the pan specified here.

Check how the pan will stand inverted before mixing the batter. Use the specified footed pan, standing securely on a level heatproof surface with the cake clear of the counter. Check that arrangement while the pan is still empty and cool.

Cool it before cutting

The bake is followed by a complete inverted cool. Loosen the cold cake carefully from the outer wall, center tube and base. Its plain ring shape is enough for serving, and a gentle sawing motion with a serrated knife is kinder than pressing down hard.

Passover preparation concerns the ingredients and equipment as well as the source of lift. Choose potato starch and processed ingredients appropriate to the intended household's practice and use suitable equipment. Its lightness comes from the eggs. Lemon gives the otherwise plain cake its citrus flavor.

Explore the historical background and companion recipes in Time, Texture and Tradition: Jewish Cooking Techniques Across the Ages.