Preheat the oven to 160° traditional heat. Grease a 27x10x8cm cake mold. Line it with baking paper to make unmolding easier.
In a saucepan, heat the milk, honey, butter and orange zest while mixing. Stop when boiling.
In a bowl, combine the flour, brown sugar, 4-spice mix, vanilla extract, baking soda, baking powder and salt. Make a well in the middle of the dry ingredients.
Pour the milk in 3 batches into the center of the dry ingredients, mixing between each addition to obtain a smooth paste. Do not overmix, just enough to no longer see any flour.
Pour the dough into the mold then bake for 1 hour. Test for good cooking by inserting a wooden pick which should come out dry. If it is not yet cooked, continue for a few minutes.
Leave to cool then turn out onto a rack. Once cooled, wrap the gingerbread in cling film then in an airtight box or aluminum foil - important so that it retains its softness. If possible, wait 24 hours to taste it, until it develops its full aroma.
Notes
Gingerbread will keep for around 10 days, but for this you must wrap it in cling film once cooled and place it in an airtight box or surround it with aluminum foil.Want to cover it with a shiny topping? In a saucepan, bring 25g of honey to the boil with 15g of water. Brush over the warm gingerbread.