In a large bowl combine together 230g of softened butter with 150g of caster sugar and 210g of brown sugar.
Add to this the two eggs and 1 teaspoon of vanilla extract, mix well.
In a bowl add together 250g of plain flour, 1 teaspoon of bicarbonate of soda, 1 teaspoon of salt, 1 and a half teaspoon of ground cinnamon and mix together.
Add the two bowls together, mixing thoroughly.
Add to this 250g of quick cooking oats and mix together. Cover the bowl with cling film and put in the fridge for 1 hour.
Preheat the oven to gas mark 5 / 190*C / 374 F.
Using Bakewell baking paper, line a baking tray.
Roll the mixture into golf ball sized balls and place on the lined baking tray. leaving a small gap between each ball.
Place tray in the middle of the oven and bake for 9-10 minutes.
Once the time is up, remove cookies from tray and place on a wire rack to cool before eating.