Line an 8 x 8 inch square tin with greaseproof paper and dust lightly with icing sugar and a tbsp of cornflour. Set aside.

Clean a mixing bowl and whisk attachment with lemon juice or white wine vinegar to remove any grease. Using this whisk attached to an electric mixer, whisk the egg white in the cleaned mixing bowl until it has reached stiff peaks. Set aside for now.

Put the caster sugar, 90 ml of water and liquid glucose in a saucepan and stir until it is all combined. Turn the heat up to medium - high to bring to the boil. Swill the saucepan around every now and again to distribute the heat evenly.

Once the syrup is boiling, turn the heat down to medium and put a lid over the saucepan. Leave to cook for 2 minutes. After 2 minutes, check that there are no sugar crystals around the side of the saucepan. If there are sugar crystals, place the lid back over the saucepan for another 2 minutes and allow the condensation to wash down the sugar crystals.

While the syrup is cooking, pour the other 90 ml of water into a large mixing bowl and sprinkle the gelatin/agar-agar over it. Give it a quick mix with a fork and leave to bloom for at least 10 minutes.

Once there are no crystals left around the side of your saucepan, leave the syrup to cook over a medium heat until it has reached 116°C [240°F] according to a sugar thermometer.

To test if the syrup is ready without a thermometer, leave to cook for 5 minutes and then add a small amount of the syrup to a small jug or bowl with cold water in. If the syrup turns into a clear shape in the water and you can form a firm but pliable ball with it in your hands, it’s ready. If it can be flattened immediately, it’s too soft so check again after 5 minutes. If it is hard and barely pliable, it’s a little overdone but still usable. It should be ready after about 10 minutes of cooking. See the Top Tips section for more information on this.

Once the syrup is ready, remove from the heat and take off the lid. Allow the bubbles to dissipate.

Whilst whisking on a low - medium speed, pour the syrup down the side of the mixing bowl with the gelatin mix. Pouring it down the side of the bowl and not directly into the gelatin/agar-agar mix avoids scorching. Whisk on a medium - high speed to combine the syrup and gelatin/agar-agar, then continue whisking until the mixture is white and light and has doubled in size (around 5 minutes).

Add the salt and vanilla extract and whisk in. Drop in some of the purple food colouring - start light and add as you whisk if necessary. You can add more later.

If using it, whisk in the egg white you whisked to stiff peaks earlier.

Spoon the marshmallow mixture into your lined tin and smooth over with a well oiled spatula. Leave to set for at least four hours at room temperature. Mine took about 6 hours to set fully. It can take less or more time, depending on the thickness of your marshmallow, especially if you are making more than the recipe stated.

Once set, oil a flower shaped cookie cutter (oil multiple sizes if desired) and use it to cut out pieces of marshmallow. Be sure to clean and oil your cookie cutter(s) in between each marshmallow to avoid ripping as much as possible.

Toss the marshmallows in a small amount of icing sugar, brush off the excess with your finger and then store in an airtight container until ready to decorate.

When ready to decorate, use a thin paint brush or cocktail stick to carefully paint LSP’s facial detail on each marshmallow piece with the black food paint. Finish by sticking a yellow star to the forehead area of each purple marshmallow.