Preheat your oven to 350°F (175°C) and set aside an ungreased 10-inch tube pan.

Sift 1 cup of cake flour into a bowl and set it aside.

In another mixing bowl, combine 12 large egg whites and whip until frothy. Add 1 teaspoon cream of tartar and a pinch of salt, beating until soft peaks form.

Gradually add 1 cup of granulated sugar while mixing until stiff peaks form.

Gently fold in the sifted cake flour and 1 teaspoon vanilla extract.

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

Bake for 30-35 minutes or until golden brown and a toothpick comes out clean.

Invert the pan onto a wire rack to cool completely for 1-2 hours.

Prepare the raspberry swirl by mixing 1 cup of raspberries with 1-2 tablespoons of granulated sugar. Let sit for 10 minutes.

Once cooled, transfer the cake to a serving plate. Top each slice with whipped cream and drizzle the raspberry swirl over it.