Instructions:
Preheat the oven to 350°F (180°C). Grease and flour a 9-inch (23 cm) round cake pan.
In a large bowl, cream together the butter and white sugar until light and fluffy. Beat in the egg yolks, one at a time, until fully incorporated.
In a separate bowl, whisk the egg whites with the cream of tartar until stiff peaks form.
In another bowl, sift together the cake flour, baking powder, and salt.
Gradually add the flour mixture to the butter mixture, alternating with the fresh orange juice, until just combined.
To the instructions
