This is very sweet and very morerish...my husband ate four slices in one sitting...(to be fair they weren't huge pieces!)
200g (8oz) butter, softened 200g (8oz) soft brown sugar 2 egg yolks 100g (4oz) plain (all purpose) flour 100g (4oz) porridge oats
Preheat the oven to 190C/375F/Gas 5. Grease a 9" square baking tin and line with baking parchment.
Beat together the butter, sugar and egg yolks until light and smooth.
Add in the flour and oats and mix well.
Press into the prepared tin and bake for 20 minutes until lightly browned. Remove from the oven and leave to cool slightly in the tin. While still warm cut into slices and leave in the tin until completely cold.
You can add a heaped tablespoon of chocolate chips into the mixture or I like to add a chopped up Milky Way or Mars bar. You could also add in chopped nuts or dried fruit.