If necessary, the day before, beat the egg whites with 1 pinch of salt until stiff for the meringue spirits, while pouring in 100 g of sugar. Continue beating until the sugar has dissolved and a shiny mass has formed.
Preheat oven (electric cooker: 100 °C/circulating air: 75 °C/gas: see manufacturer). Line baking tray with baking paper. Fill egg whites into a piping bag with a perforated nozzle (13 mm Ø), spray approx. 12 tuffs onto the baking tray.
Leave to dry in a hot oven on the lowest shelf for approx. 1 1⁄2 hours. Then cool down in the switched off oven for approx. 1 hour and let it dry again. Leave the oven door ajar while doing so.
The next day, grease a springform pan (20 cm Ø) for the cake and dust with a little flour. Preheat the oven (electric cooker: 175 °C/circulating air: 150 °C/gas: see manufacturer). Dab the beetroot dry, cut it smaller and puree it finely with oil in a bowl.
Mix in 3 eggs one after the other with the whisks of the mixer. Mix 150 g flour, baking powder, cocoa, 175 g sugar and vanilla sugar. Stir with the beetroot mix. Fill the dough into the form. Bake in a hot oven for about 40 minutes.
Remove from the mould and leave to cool for about 15 minutes. Then remove and let it cool down.
Roughly chop the chocolate coating. Heat the cream in a small pot. Remove from heat. Melt the couverture and coconut oil in the cream while stirring, chill for about 10 minutes. Spread the cake with the chocolate cream, except for 1 tablespoon for decoration, all around.
Fill the rest of the cream into the disposable piping bag, cut off the tip just short. Spray the Baisertuffs dots as faces. Leave to dry. Decorate the cake with meringue ghosts.