Rachel Allen's orange and almond syrup cake is finished with dark chocolate orange icing.
Preheat the oven to 160C/140C fan/gas 3. Butter the sides of a 20cm cake tin and line the base with a disc of baking parchment.
Place the butter, sugar and orange zest in a large bowl and beat together until soft and creamy. Add half the ground almonds and continue to mix, then add the eggs, a little at a time, making sure they’re well mixed in.
Sift in the flour, baking powder and salt and add the rest of the almonds, folding these in until combined. Tip the cake batter into the prepared tin, spreading it out and levelling the top with a spatula or palette knife.
Bake for 45-50 minutes, or until a skewer inserted into the centre comes out with just a small amount of moisture sticking to it.
For the syrup: While the cake is cooking, make the syrup. Place the orange juice and sugar in a saucepan. Stir until mixed and bring to the boil. Allow to boil for just 1 minute, then remove from the heat and set aside.
When the cake is cooked, take it out of the oven and let it sit in the tin for just 5 minutes. Loosening around the edges using a small, sharp knife, carefully remove the cake from the tin and transfer to a serving plate.
Straight away pour the hot syrup over the cake - reheat the syrup if it has had a chance to cool down. Leave to cool completely while soaking up the syrup.
For the icing: Place the butter in a heatproof bowl with the chocolate and orange liqueur or orange juice and set over a saucepan of simmering water.
Leave just until melted, stirring occasionally, then pour the icing over the cake. This is a wet icing so don’t worry if it drips down the sides of the cake. Let the icing set and then decorate with pieces of crystallised orange peel, if you wish.