Gateau Nantais or Somewhere Near It

First of all I feel I should apologise to the people of Nantes (perhaps I should apologise to all the people of Brittany and even the entire population of France, just to be on the safe side). The reason being that Gateau Nantais is a traditional recipe which I have to admit that I've tweaked a bit. The traditional and authentic version tends to be quite heavily flavoured with rum – there's more rum in both the mixture and the syrup and an icing made purely with rum and no water.

So, a lot of rum, then. My version is more lightly flavoured with rum, which means that the almond taste is more prominent. Anyway, this is the version I like, either as a dessert or with a cup of tea.

For the gateau:
    125 g butter, softened (the bakers of Nantes would, I feel sure, only use salted butter)
    150 g caster sugar
    100 g ground almonds
    3 eggs, lightly beaten
    40 g plain flour
    2 tsp dark rum
    a few drops of almond extract

For the syrup:
    4 tbsp water
    2 tbsp caster sugar
    2 tsp dark rum

For the icing:
    100 g icing sugar
    2 tsp dark rum
    2 – 3 tsp water

Preheat the oven to 170°C. Butter and line a 22 cm cake tin – do this fairly thoroughly because the gateau does like to stick. A springform tin is probably ideal, since the gateau is best removed from the tin while still warm.

Mixing the cake is made easier by using the paddle attachment on an electric mixer but it's certainly not essential. Cream the butter and sugar together thoroughly. Briefly beat in the ground almonds. Beat in the eggs a little at a time (in at least 3 parts). Finally, sieve the flour over the mixture and gently fold it in together with the rum and the almond extract.

Put the mixture into the prepared tin and spread it out as evenly as possible. Bake in the preheated oven for 40 – 45 minutes. The gateau should look a light golden colour, so if it seems to be browning too quickly after 25 minutes or so (and in my experience there's a good chance that it will) then cover the tin loosely with some foil.

While the gateau's baking, make the syrup. Add the sugar and water to a small saucepan and heat, stirring all the time, until the sugar dissolves. Bring to the boil and boil for 30 seconds or so. Take off the heat and stir in the rum.

Once the gateau is evenly golden and no longer squidgy, take it out of the oven and, as soon as you dare, remove it from the tin and place on a cooling rack. Paint the rum syrup evenly over the top of the gateau while the syrup is still warm and the gateau is still hot from the oven. Leave to cool completely.

Once the gateau is cold, mix the rum into the icing sugar and add as much water as needed to make a smooth icing which is not too runny (around 2½ tsp should be about right). Spread the icing evenly over the gateau and don't worry too much if a bit dribbles down the edge.