Preheat oven to 180 C. Grease and line one 15 inch baking pan and line the bottom of pan with parchment or wax paper.
In a bowl, sift the flour, salt, corn flour and cocoa powder.
Separate egg whites from yolks (make sure there are no traces of yolk in whites, otherwise it will be difficult to beat into a white mixture).
In a large bowl, beat Egg Yolks and 3 Tbsp Sugar until smooth, creamy and light yellow (approx 5 minutes). Add Vanilla and mix through.
In a clean mixing bowl, with the whisk attachment beat the egg whites until foamy. Add the sugar and beat at medium-high speed until stiff peaks form.
Add 1/3 Egg Whites mixture into Egg Yolk mixture and gently fold in.
Then sift about 1/2 of the flour mixture over the egg mixture using a rubber spatula or whisk.
Add 1/3 Egg Whites and continue to fold in.
Add remaining Flour/Corn Starch mixture and continue to fold in.
Add remaining Egg Whites and gently fold in until entire batter is evenly mixed.
Pour into your pan, smoothing the top.
Bake for about 10 minutes or until a toothpick inserted into the center comes out clean.
Remove cake from pan (with parchment paper) and place on a cooling rack for 5 min and remove the parchment paper.
Dust a clean towel or parchment paper with icing sugar. Place the cake over the icing sugar and starting from the short end, roll up cake in towel. Set aside until cool completely.
now unroll cooled cake and spread evenly with ice cream. And spread some nuts. Roll up cake again.
Now wrap tightly in parchment paper or plastic wrap and then freeze overnight until firm.
Place cake on a wire rack over a tray or waxed paper. Dust some cocoa powder or icing sugar over the top.
Cut into 1/2inch layer with a Sharpe knife and serve immediately.