Preheat oven to 350°F (175°C). Grease and flour two 9-inch pans. Mix cake flour, baking powder, salt, and ground walnuts in a bowl.

Whip 1 ½ cups heavy cream until stiff peaks form. Combine white sugar, eggs, and vanilla extract in a large bowl. Beat 5 minutes, then fold in flour mixture alternately with whipped cream.

Pour batter into prepared pans. Bake for 25 to 30 minutes or until a toothpick comes out clean. Cool in pans for 15 minutes, then transfer to a wire rack and cool completely.

Combine cream cheese, white sugar, salt, and vanilla extract in a bowl. Beat until smooth. Whip 1 ½ cups heavy cream until stiff peaks form, then fold into cream cheese mixture.