Step 2

Grease and line a 16x26cm slice tin with baking paper with the long sides extending over the sides.

Step 4

Place the butter, condensed milk, sugar and maple syrup in a large microwave-safe bowl and microwave for 2 minutes. Stir the mixture and repeat twice (6 minutes total). Take it out and stir it again then microwave for 1 more minute. Add the chopped chocolate and vanilla and leave to sit for 1 minute then whisk through until the mixture is smooth and glossy. Spoon it into the tin and spread it out so the top is smooth.

Step 6

Leave out on the bench until cool and then refrigerate. Slice into 36 squares before serving. Keep chilled until serving.