Kilo Keki — Turkish Equal-Weight Butter Cake

Beat the butter and sugar together at high speed for 8 minutes, until the color changes from yellow to cream and the volume increases noticeably. This cake has no baking powder; all of its rise comes from the air trapped in the butter during this step. Scrape down the sides of the bowl twice with a spatula.

Sift in the flour, salt, and lemon zest. Fold with a spatula from the bottom up until no flour is visible. Do not use a mixer; at this stage it would develop the gluten and knock out the air.

Pour the batter into a greased and floured loaf pan, then make a shallow dip in the surface from the center toward the edges. The dense batter rises in the center, and this dip helps the cake bake level.

Bake in an oven preheated to 160°C / 320°F for 55 minutes. Use 160°C / 320°F rather than the usual 175°C / 345°F because the batter is dense and, at a higher temperature, the outside would brown while the center remained raw. It is done when a toothpick inserted in the center comes out clean. Let it cool in the pan for 20 minutes, then transfer to a wire rack.