Preheat the oven and prepare the baking pan as needed.

In a bowl, whip the egg whites with cream of tartar until soft peaks form.

Gradually add the granulated sugar and continue to whip until stiff peaks form.

Sift together the cake flour and gently fold it into the egg white mixture.

Add vanilla extract and mix gently to combine.

Pour the batter into the prepared pan and smooth the top.

Bake in the preheated oven for approximately 40 minutes or until golden and a toothpick comes out clean.

Allow to cool upside down in the pan before removing.

Serve topped with fresh berries and whipped cream.