Kue Sifon Jeruk

Instructions

1. Preheat the oven to 170°C (325°F). Prepare a 9-inch (22 cm) tube pan, ungreased. To make the egg yolk batter, beat the egg yolks with sugar until pale, then add the salt and oil, mixing briefly until it resembles mayonnaise.
2. Add the grated orange rind, orange juice, and orange coloring, and mix well. Fold in the sifted flour until a batter forms.
3. To make the egg white foam, beat the egg whites and cream of tartar until the mixture forms soft peaks. Gradually add the sugar, beating at high speed until stiff peaks form. Gently fold the beaten egg white foam into the egg yolk batter in three batches until fully combined (do not overmix).
4. Pour the batter into the ungreased 9-inch (22 cm) tube pan. Tap the pan a few times on the tabletop to remove any trapped air bubbles in the batter. Bake in the preheated oven at 170°C (325°F) for 50-60 minutes, or until cooked. (When lightly pressed, the cake will spring back.) Immediately upon removing the cake from the oven, invert the pan (turn it upside down) and place it on a bottle or flat surface so it is suspended above the counter. Let it cool completely before removing the cake from the pan. To remove the cake from the pan, run a thin-bladed knife or a palette knife around the sides of the pan and the center core to release the cake. Then, run the knife along the base of the pan to remove the cake.