Rub the butter and flour together to make a crumble mixture.
Stir in the ground almonds and lemon zest.
Beat the eggs in a bowl with the syrup until combined
Add the egg mixture to the flour and combine with a fork. The mixture will become quite lumpy - which is fine!
Roughly spread the mixture into a greased loose-bottomed 8" cake tin. Do not press the mixture down.
Bake at 180 degrees (gas 4) for 30 - 40 minutes until golden and brown and firm.
Leave to cool in the tin for a little while and then turn out to further cool on a wire tray.
This cake is traditionally never sliced, serve broken into pieces to share.