Preheat the oven to 200°F. Fill a medium saucepan with about 2 inches of water and bring to a gentle simmer over medium heat.
Prepare the bowl of a standing mixer by thoroughly wiping the inside with a paper towel dampened with white vinegar. Add the egg whites, sugar, and cream of tartar. Place the bowl over the saucepan of gently simmering water, making sure the bottom of the bowl does not touch the water. Whisk constantly, until the sugar has completely dissolved, about 5-7 minutes. To check if it is ready, rub a bit of the mixture between two fingers; if you do not feel any grains of sugar, then the sugar has dissolved. Make sure to whisk constantly during this step because if left unattended, the bowl can become too hot and the eggs will start to cook.
Transfer the bowl to the standing mixer fitted with a whisk attachment. Whisk for about 10 minutes, starting on low speed and gradually increasing to high, until the whites increase in volume and form glossy, stiff peaks.
While the meringue is whipping, line three baking sheets with parchment paper. On one, draw a circle of 10 inches in diameter, on another draw a circle of 8 inches and on the last sheet draw two circles, one of 6 inches and another of 4 inches.
Once the meringue is done, spread it over each traced circle to form a disc of meringue. You can use a pastry bag or a spatula to do this. For the smallest circle of meringue, which will be the top of your cake, I use a large spoon to dollop the remaining meringue onto the parchment so it has some height. Bake in the oven until the meringues are dry and can be easily lifted from the parchment paper, but are still white in color, about 2 to 2 ½ hours. The larger discs of meringue will take longer to bake. Remove from the oven and allow to cool on the sheets placed on wire racks for at least two hours.
When ready to assemble your dessert, whisk together the heavy cream and the seeds from the vanilla bean in a cold bowl until soft peaks form.
To assemble your tower place the largest meringue disc on your serving platter. Top with a third of the whipped cream and sprinkle with a third of the pomegranate and passion fruit seeds. Top with the second largest meringue disc, and add another layer of whipped cream and seeds. Repeat with the third layer and top the cake with the smallest and last disc. Decorate around the edges of the cake with the fresh mint, red currants and husk cherries. Serve immediately.
For this recipe it is critical that you use a very clean bowl, free of all grease, to whip your egg whites. This is why you clean out the bowl with vinegar. Do not skip this step or all your time and egg whites will go to waste!