Prepare jelly roll pan linin it with waxed paper or parchment paper, and butter the paper. This ensures it is easy to get the cake roll out of the pan. I just use a cookie sheet with edges, it doesnâ€™t have to be a jelly roll pan.
Preheat the oven to 375, and separate the 4 eggs.
Whip the 4 egg whites until stiff, then pour onto a plate and set aside. I always do the egg whites first, because then I donâ€™t have to wash out the mixer bowl.
Put the 4 egg yolks in a mixer bowl with the sugar and beat until creamy. Add the vanilla and beat again.
In a separate bowl combine the flour, salt and baking powder.
Now fold the egg whites into the egg yolk mixture while sifting the flour over the top, stirring gently with a spatula.
Spread evenly in the prepared pan and bake for 12 minutes, until it is light brown.
Turn onto a towel dusted with powdered sugar, and roll up the long way inside the towel. This helps it keep its shape once it is filled.
Once it has completely cooled inside the towel unroll the sponge cake, and spread with whipped cream and strawberries. Roll it back up and serve with more strawberries and cream.