Combine icing sugar and cornflour. Oil a 20x20cm tin and dust with the sugar-cornflour mixture.

Grate the beetroot and steep in 125ml hot water for 30 seconds. Strain the pink water, add gelatine and stir until dissolved.

Heat sugar with 250ml water in a pan with a sugar thermometer. Bring to 122°C (hard ball stage).

Take pan off heat and stir in the gelatine mixture.

Whisk egg whites until stiff. Turn mixer to slow and trickle in the hot sugar solution.

Continue beating until mixture is very thick and leaves a ribbon trail — about 10 minutes. Pour into prepared tin while still pourable.

Leave in a cool place (not fridge) for at least 2 hours to set.

Dust top with cornflour mix. Loosen edges with oiled knife. Turn out, coat hands in cornflour mix, and carefully remove from tin. Cut into cubes with oiled knife, dusting cut surfaces immediately.