Preheat your oven to 180°C (160°C Fan, gas mark 4) and line a baking tin with parchment paper. I used an 8″ (20cm) baking tin.
Add butter, light brown sugar and golden syrup to a mixing bowl and melt it in a microwave or a saucepan on a medium heat.
250 g Butter, 175 g Light Brown Sugar, 50 g Golden Syrup
Add vanilla extract, porridge oats and raspberries to the melted mixture and mix it gently until the mixture is evenly blended. Note: Set a handful of raspberries aside.
350 g Porridge Oats, 200 g Raspberries, 1 tsp Vanilla Extract
Pour the flapjack mixture into the lined baking tin and spread it evenly into all four corners then top with the remaining raspberries.
Use the back of a spoon to press the flapjack mixture down.
Bake it in the oven for 40 minutes or until the corners are golden brown. Once baked, allow the flapjacks to cool down before cutting it into slices.
Video
Notes
I cut my flapjack into 9 chunky squares, but you can cut them into smaller slices or rectangles if you wish.