Preheat your oven to 350°F (175°C) and prepare a 10-inch tube pan without greasing it.

Whip the room temperature egg whites with an electric mixer on medium speed until soft peaks form, about 2-3 minutes.

Gradually add in the granulated sugar, beating on high until glossy stiff peaks form, taking another 2-3 minutes.

Sift the cake flour over the whipped egg whites and gently fold it in with a spatula.

Carefully fold in the crushed raspberries, ensuring they are evenly distributed.

Pour the batter into the tube pan, smoothing the top, and tap the pan to remove air bubbles.

Bake for 30-35 minutes until the cake springs back lightly when touched and is golden-brown.

Remove the pan and immediately invert it onto a bottle or cooling rack to cool completely.

Once cool, remove from the pan, dust with powdered sugar, and serve with whipped cream and extra raspberries if desired.