Classic Coffee Cake (Loaf)

You will need 1 x 20cm square cake tin

225g soft butter

225g caster sugar

4 organic eggs

225g plain white flour, preferably unbleached

1 tsp baking powder

scant 2 tbsp Irel or Camp coffee essence

For the coffee buttercream:

150g butter

330g icing sugar, sieved

5-6 tsp Irel or Camp coffee essence

For the coffee glacé icing:

450g icing sugar

scant 2 tbsp Irel or Camp coffee essence

about 4 tbsp boiling water

To decorate:

Caramelised walnuts or just use walnut halves

For caramelised walnuts:

100g sugar

50ml cold water

20 walnut halves

225ml hot water