bergamort cake from the art of cooking

ingredients:
4 eggs (about 240 grams)
240 gr of sugar
240 gr of flour
240 gr of butter
2 organic bergamot (zest and juice)
50g raisins dried currants
1 pinch of salt
method:

Preheat oven) 180.
In a bowl, work the softened butter with the sugar and stir until cream.
Break and separate the yolks from the egg whites. Add yolks to the butter-based preparation.
Add the zest and juice of bergamot. Put the flour at once and stir.
Beat the egg whites until stiff, adding a pinch of salt. Stir in the preparation gently lifting it with a spatula.
Put the raisins at the last minute and stir gently.
Pour into a loaf pan lined with a baking paper.
Bake for 40 minutes baking at 180 °. Check baking your cake by driving in the center of a heated knife blade or the tip of a large needle. Remove from oven and let cool.
http://cuisinedetouslesjours.com/2012/02/27/quatrequartalabergamoterhumetraisins/