Pre heat the oven to 140.
Place the demerara sugar in a food processor and grind to a finer powder (you could also use golden caster sugar for this recipe, in which case this step can be skipped)
Place the egg whites in a clean mixing bowl in a stand mixer. Whisk until they form soft peaks. With the whisk running, add the sugar a spoonfull at a time until it is all incorporated.
Line a baking sheet with ligtly oiled greaseproof paper and spoon the mixture to form 6cm rounds.
Cook in the oven for 45min. Then turn the oven off and leave the meringues to cool inside.
Line a 3cm deep tray with clingfilm.
Bring the 100ml of Campari, 150ml of orange juice and 50g of sugar to a boil.
Turn down to a simmer, then whisk in the agar agar.
Continue to cook gently for a couple of minutes until the agar agar and sugar have dissolved.
Pour into the tray . The jelly needs to be at least 1cm deep.
Cool slightly, then refrigerate until set. This will take around 1.5 hours.
When set, turn out and cut into cubes
Place the remaining 100ml of orange juice, 50 ml Campari and 30g sugar in a saucepan, bring to a boil and reduce by 2/3.
Pour into a flat tray to cool.
Peel and segment the orange using a small, sharp knife. Remove any pips, then drop into the cooled Campari syrup.
Place the cream and icing sugar in a large bowl and whisk to soft peeks.
Remove the jelly from the tray and cut into 1cm cubes.
Place the meringue on a plate. Arrange some jelly cubes and orange segments around and on top of the meringue. Drizzle with a little of the Campari syrup and top with the whipped cream.
«The meringues can be stored in an airtight and dry container for about 3 days. It is very important not to cool the jelly in the freezer: agar agar does not freeze well, and the jelly will split if allowed to freeze.»