For the cranberry filling:
- Add filling ingredients to a medium pot and bring to a simmer over medium-high heat. Simmer for 8-10 minutes until cranberries burst and soften completely. Then cool slightly and puree in a blender or with an immersion blender. You can optionally leave it chunky, but I think it’s best smooth.
- Chill filling before using it.
For the Sponge Cake:
- Preheat oven to 350 degrees F. Separate your eggs into yolks and whites. Add the whites to a mixing bowl with a whisk attachment (or use a hand mixer) to beat the eggs. Add 1/4 cup sugar and beat until the eggs hold stiff peaks.
- In a separate bowl, sift together the flours, baking powder, and salt.
- In a third bowl, whisk together the egg yolks, 1/2 cup sugar, and vanilla. Whisk until they are combined completely and not grainy.
- When egg whites are stiff, add about two cups of egg whites to the yolk mixture and whisk together to lighten the yolks. Then gently fold the yolk mixture back into the egg whites, trying to keep it as light as possible.
- Finally, fold in the dry ingredients. Be gentle with the batter to preserve as much lightness as possible. Don’t overwork it, but make sure the flour is incorporated. Don’t stir. Fold.
- Pour batter into a 9×13 rimmed baking sheet (quarter sheet size) that has been lined with parchment paper and greased lightly.
- Bake the sponge cake for about 18-20 minutes until it’s browned lightly and springs back when poked.
How to Make the Roll:
- When the sponge cake comes out of the oven, dust the top of the cake with powdered sugar and cover it with a clean towel. Then flip it over and remove the baking sheet. Peel off the parchment and dust heavily with powdered sugar on that side. Roll the sponge cake, while still hot, starting from the short end. The towel should get rolled up with the cake to create some space between the cake and to prevent sticking.
- Place the rolled cake in the fridge to cool, at least 30 minutes.
- To prepare the filling, make whipped cream and then lighten the filling by stirring in 1 cup of whipped cream to the cranberry filling.
- Unroll the cake and spread a thin layer of filling on the cake, leaving a little room around the edges.
- Re-roll the swiss roll and dust with powdered sugar.
- Top Swiss roll with whipped cream, orange zest and any fruit you like.
Slice and serve!