Method

1. Grease and line a deep 11-inch square baking tin with parchment paper. Combine the water, sugar, vanilla and condensed milk in a large, heavy-based saucepan.
2. Slowly bring to a boil while stirring constantly.
3. Add the corn syrup and maple syrup and continue cooking over medium heat while stirring until the mixture reaches 230°F. If you don’t have a sugar thermometer test the mixture by drizzling a small amount of the sugar syrup from a spoon into a cup of cold water - the syrup will form fine threads instead of dissolving away in the water instantly.
4. Add the butter and cook until 245°F or until the syrup forms a firm ball when dropped into a cup of cool water.
5. Immediately pour the mixture into the prepared tin and allow to cool completely.
6. Cut the toffee into rectangles.
7. Store in an airtight container, in a cool place (not the fridge) for up to two weeks.