Whisk the flour, baking powder and salt in a bowl. Set aside.

In a stand mixer with the whisk attachment, beat the butter and sugar on high for 3–4 minutes, until pale and creamy. Add the orange zest, cinnamon, clove and vanilla and beat to combine.

Add the egg yolks one at a time, letting each one mix in before adding the next.

In a separate clean bowl, whip the egg whites on medium speed until tripled in volume, white, with soft peaks. Set aside.

Stir the baking soda into the orange juice; it will foam. With the mixer on low, add it to the batter.

Add the flour mixture in parts, alternating with the milk and brandy: flour, milk, flour, brandy, then the rest of the flour.

Mix in the walnuts on low speed.

Remove the bowl from the mixer. Fold in the egg whites by hand, one heaping spoonful at a time. Be gentle and don't rush.

Drop the foil-wrapped coin into the batter and pour the batter into the pan.

Bake for 50–60 minutes, until golden and a tester inserted in the center comes out clean.

Cool in the pan for 15 minutes, then unmold, peel off the parchment and set the cake on a platter. Let it cool completely.

Dust with powdered sugar and decorate as you like. Cut at midnight on New Year's Eve or on New Year's Day. Whoever finds the coin is lucky all year!