How to prepare
Make the cake
- Preheat oven to 160C Fan /180C/350F/GM4
- Combine flour, ground walnuts, ground coffee and salt in a bowl.
- In a large bowl or food mixer, cream butter and sugar until pale and fluffy.
- On medium speed, add eggs a tablespoon at a time, mixing well between each addition. Add a teaspoon of the flour mixture if the cake batter looks like curdling.
- On the lowest speed, add the flour mixture until just combined (10 secs).
- Evenly fill the tins (weigh each tin if you want to be precise) and smooth the surface with palette knife or back of a spoon.
- Bake in the centre of the oven for 30 until a skewer comes out cleanly and top springy to touch.
- Remove cakes from the oven, leave the cakes in the tins for a couple of minutes turn out on to a wire rack to cool completely.
- Wrap the cakes in cling film and rest overnight at room temperature before icing.
Prepare the cardamom syrup
- Place the caster sugar and water in a small saucepan and over a low heat, dissolve the sugar completely. Then bring to the boil for a couple of minutes.
- Remove from the heat, add the ground cardamom and set aside.
Make the buttercream
- Place the unsalted butter in bowl or food mixer and beat until pale and light in texture.
- Add the sifted icing sugar in 3 batches, beating well between each addition, until the buttercream has increased in volume and is very pale and fluffy.
- Add the coffee mixture and beat again to mix.
- Place one cake half upper side down on a serving plate, generously brush with the syrup.
- Sandwich the cakes together using half the buttercream.
- Place on the top layer, brush again with syrup and decorate with the remaining buttercream and walnut pieces.