Line and grease a 20cm (8inch) square pan with baking/parchment paper. *See notes.
Prepare the bicarbonate of soda and place it to one side for later.
In a tall, medium sized heavy based saucepan, add the sugar, honey and 2 tbsp of water and place the sugar thermometer to the side. Put it on a medium heat, until all of the sugar has dissolved. Try not to let the mixture bubble until the sugar has disappeared and if you need to give it a stir, use a heat-proof spatula. Scrape down the sides of the pan if the sugar comes up, as sugar crystals are your enemy and will cause it to be grainy. Be extra careful as it will be extremely hot.
Once completely melted, turn up the heat slightly and simmer for 8-12 minutes, until you have an amber coloured caramel. (Avoid stirring as it will create sugar crystals.) If you have a sugar thermometer you want it to reach 149°C / 300°F, also known as hard crack.
Then as quickly as you can, tip in the bicarbonate of soda and whisk for 3-4 seconds, until it has all disappeared and the mixture is foaming. Be careful as it will bubble up and expand quickly.
Immediately, pour into your lined greased pan as quickly as possible. Leave to cool fully for about 30-60 minutes.
Once cool, remove from the pan and break it into lots of pieces.
Chocolate coating: Melt some chocolate in a small heat proof bowl over a pan of simmering water. Make sure the bowl is not touching the water. Once melted, dip your honeycomb into the chocolate and leave to cool on a wire rack or some greaseproof paper. Enjoy.