In a large bowl add in the sugar, butter, and egg yolks and beat until well combined. In a smaller bowl whisk the egg whites into a smooth meringue. Add half of the meringue into the mix and continue beating, slowly pour the rest of the meringue and whisk until it has become one smooth mixture. Toss in the walnuts, the flour, baking powder, and the rest of the ingredients, and beat until it has become one big mass.

Tip: Add the baking powder into the flour and mix together before adding into the egg mix. I also add a bit of Cognac in the mixture before baking because it gives the cake a bit more of a taste of Cognac. 🙂