Easy Cloud Cake

Preheat your oven to 325°F (163°C). Leave a 9-inch round cake pan completely ungreased. Separate 6 room-temperature eggs, placing whites in a grease-free bowl and yolks in a medium bowl. Ensure zero yolk fat gets into the whites.

In the yolk bowl, whisk together the 6 egg yolks, ¼ cup of the sugar, ½ teaspoon of vanilla extract, and a pinch of salt until pale and slightly thickened. Gently fold in the ½ cup of sifted flour until just combined.

Add the ¼ teaspoon of cream of tartar to the egg whites. Beat on medium speed until foamy. Gradually stream in the remaining ¼ cup of sugar while increasing speed to high. Beat until stiff, glossy peaks form that hold their shape without looking dry or clumpy.

Gently stir one-third of the whipped whites into the yolk mixture to loosen its density. Add the remaining egg whites in two additions, using a sweeping downward-and-over folding motion with a spatula just until integrated. Do not overmix.

Pour the airy batter into the ungreased cake pan and smooth the top lightly. Bake at 325°F (163°C) for 35 minutes until the top springs back when touched gently and a toothpick inserted in the center comes out clean.

Immediately invert the hot cake pan over a wire rack or bottle neck so the cake cools upside down for 30 minutes. Run a thin knife around the interior edges to release the cake, then turn onto a serving plate.