Preheat the oven to 180°C / 350°F / Gas mark 4.
Line a cupcake tin with paper cases or silicone ones ideally if you have them.
Use a large mixing bowl to whisk the margarine and the sugar until creamy.
Add the golden syrup gradually while still whisking the mixture slowly.
Take a spoon or plastic spatula and fold the mixture into itself slowly.
Add the milk and sieve in the flour a little at a time.
Add this in slowly then whisk in.
Repeat until all flour is gone and the mixture is thick and smooth.
Sieve in the cocoa a little at a time to mix it thoroughly.
Keep whisking until the whole mixture is well combined.
Add the bicarbonate of soda and the baking powder separately and keep mixing until both have been fully absorbed.
Drizzle the vanilla extract around the bowl and whisk it into the mixture.
Spoon the mixture into the cupcake cases until they are ¾ full.
Bake for 25-30 minutes.
Cool on a wire rack before serving.