Method
Pre-heat the oven to 175degC (160degC fan assisted), 350degF, gas mark 4. Lightly oil a 19cm round non-stick sandwich tin and line the bottom with baking parchment or silicon.

Put the oats into a large bowl. Add the butter, cut into large pieces, then pour over the boiling water and stir. Leave it to cool for 15 minutes or so, stirring occasionally so that the butter is melted into the mix.

Sift the flour and spices into a second bowl.

Once the oat mixture is cool, beat the eggs into it followed by the flour and spices.

Turn into the prepared tin and bake for 30-40 minutes until the top is beginning to brown and a knife inserted in the centre comes out clean.

Allow to cool in the tin for a few minutes, then turn out and place on a rack to cool completely.

Sieve the icing sugar into a bowl. Little by little beat in the lemon juice until the icing is pourable, but not runny. Put the cake, still on the rack, over a baking tray or sheet of foil to catch the drips, then pour over the icing, letting it run over the edges. Sprinkle with a little coconut if desired. Allow to set.