Always use a kitchen scale when baking, cup measuring is too unprecise.

Preheat the convection oven to 180 degrees Celsius/ 350 degrees Fahrenheit. I use the convection oven for making meringue because this allows me to bake both trays with meringue at the same time. Line two baking trays with baking paper.

Make sure that the mixing bowl and the mixing whiskers of the kitchen machine are very clean. Place the egg whites into the mixing bowl. Add the salt and start beating them until silky peaks form. Slowly, start beating in the sugar, about a third at a time, whisking very well in between, it will take about 10 minutes. It is easier to use a stand mixer.

Sprinkle the cornflour and unsweetened cocoa powder on top of the egg whites. Add the vinegar as well. Continue beating for another minute.

Divide the mixture in two and mound it onto the prepared baking trays. Form two circles of about 20 cm/ 8 inches and keep in mind that the meringues will expand in the oven, so the cake will be rather large.

Place the baking trays in the oven and IMMEDIATELY turn down the heat to 150 degrees Celsius/ 300 degrees Fahrenheit. Bake the meringues for 1 ¼ hour. Turn off the oven and leave the meringues inside the hot oven until they are completely cool. It is better to make them a day ahead so that you will not stress about them not being cool in time to serve.

Place the mascarpone, smetana or crème fraiche, icing sugar, and rose water to taste into a bowl. Mix very shortly to get the mixture smooth, but do not over mix, I find that if I mix mascarpone too long it becomes runny.

Beat the heavy cream in another bowl. Add the cream stabilizer according to the packet's instructions, that is beat the heavy creamy shortly, then slowly add the stabilizer to the cream while beating all the time until the cream has the desired consistency. If the cream stabilizer is not available, see notes.

Carefully fold the heavy cream into the mascarpone mixture. Add 1 to 3 tablespoons of lemon juice to taste.

Place one meringue onto a serving cake platter. Cover with the filling, add the second meringue on top, press slightly and sprinkle some unsweetened cocoa powder.

Keep refrigerated until ready to serve. The bezowy cake has the best consistency when eaten on the day you assemble it, but the leftovers are still delicious the next day.