Preheat the oven to 220 degrees C. Butter a deep cake pan or panettone mold
Beat the butter, eggs and egg yolks until it beomes creamy and turns into light yellow in color.
Add half of the flour to make a dough. Add half the milk and mix it well for a minute.
Add the remaining flour, milk and sugar and mix well together.
Mix until the dough becomes dry enough to handle.
Place the dough on a floured surface and add raisins, orange zest, and baking soda. Knead for another 5 to 10 minutes.
Place the dough in the baking pan and bake for 35 to 45 minutes.
Remove from the oven and let it cool.
Slice into wedges and serve.