Preheat the oven to 325°F. Place the oven rack in the center position. Use an ungreased 10-inch tube pan or chiffon cake pan.

Mix the cake flour, baking powder, salt, and ⅔ cup sugar in a large mixing bowl.

Whisk the milk, egg yolks, oil, and vanilla in a separate bowl until smooth

Pour the wet ingredients into the dry ingredients and whisk until the batter is smooth and free of lumps.

Beat the egg whites and the cream of tartar in a large, clean bowl with an electric mixer until foamy.

Gradually add the remaining ⅓ cup sugar while beating. Continue beating until stiff, glossy peaks form.

Fold one-third of the whipped egg whites into the batter to lighten it.

Gently fold in the remaining egg whites in two additions, being careful not to deflate the mixture.

Pour the batter into the ungreased pan and gently smooth the top. Tap the pan lightly on the counter once or twice to release any large air bubbles.

Bake for 40 to 45 minutes, or until the top is golden brown and springs back when lightly touched.

Remove and immediately invert the pan and allow the cake to cool completely upside down for at least 2 hours.

Once completely cool, run a thin knife or offset spatula around the outer edge and center tube. Remove the cake from the pan and release it from the base.

Serve plain, dusted with confectioners’ sugar, or topped with fresh berries and whipped cream.