Sour cream Zebra cake: why the top cracks and how to get even stripes on the cut

Classic cake with an analysis of the physics of the stripes

The outlet Life.ru has published a step-by-step recipe for sour cream Zebra cake — with an explanation of why stripes appear on the cut and what their evenness depends on. According to the publication, striped baking is a variety of marble cake that was baked in Europe as early as the late 19th century and is still made at home in Germany; in the USSR the recipe took hold because of the availability of ingredients and its festive look. The editorial team says it compared the popular versions with sour cream, kefir and milk and chose the most reliable one.

Ingredients and the key role of sour cream

Sour cream is the main ingredient in the recipe: it makes the crumb moist, fine-pored and tender. Life.ru advises using a product with at least 20% fat, since with runny sour cream the cake turns out drier. Eggs, sour cream and butter should be taken out of the fridge an hour before cooking so the batter comes out homogeneous; baking soda can replace baking powder — use half as much and don't neutralize it, as the sour cream will do the job itself. Ingredients: 4 eggs, 250 g sugar, 200 g 20% sour cream, 100 g butter, 280 g flour, 30 g cocoa, 10 g baking powder, vanilla sugar and a pinch of salt. The whole process takes about an hour, of which about twenty minutes at the stove.

How to get even rings

The key rule of the recipe: both halves of the batter — the light and the chocolate one — must be equally thick, so you add to the light half as much flour as the cocoa used in the dark one. Don't smooth the batter in the pan: each new portion presses down on the previous one with its weight and pushes it toward the walls, and that's how rings grow on the bottom, which rise in the oven and turn into stripes. The more precisely the spoon lands in the center of the spot, the even the pattern; if you miss, the rings stretch into ovals. If you pour both halves at once, you'll get a marbled cut with chaotic swirls. For a pattern on the surface, the outlet advises drawing lines with a skewer from the center to the edges, wiping it each time.

The oven, the crack and batter variations

Baking is recommended for 45–50 minutes at 180 °C in a 22–24 cm springform pan; in a narrow, tall pan the cake bakes longer, sometimes up to an hour, in a wide, shallow one — faster. For the first half hour it's best not to open the door, otherwise the center may collapse. The crack on top, according to the publication, is almost inevitable: the crust sets before the middle rises; if it bothers you, lower the heat to 170 °C and bake longer. When comparing the bases, it turned out that with sour cream the crumb is the most tender and moist, with kefir the cake is lighter, more porous and slightly tangy, and the milk version is closer to a dense pound cake; there is also a Lenten version with vegetable oil, no eggs and no dairy. The amount of sugar varies between recipes by almost a factor of two — the editorial team settled on the middle so the cake wouldn't come out cloying.

Serving

The simplest serving is powdered sugar on the cooled cake: the dark stripes on the cut become more contrasting. A more festive option is to slice the cake lengthwise into two layers, spread with sour cream mixed with sugar, drizzle with chocolate glaze made of cocoa, sugar, sour cream and butter, and sprinkle with chopped nuts: that way, instead of a cake for tea, you get a whole cake, for example for a birthday or New Year.