Grease the baking pan with butter and sprinkle with breadcrumbs or flour (you can also line it with baking paper instead).

Preheat the oven to 180 degrees (top/bottom heat mode).

Wash the plums, cut them in half, remove the pits, and cut the fruit in half again - you will get 4 pieces from each plum.

Sift the flour together with the baking powder through a sieve.

Beat the butter together with sugar and vanilla (or lemon zest) into a white and fluffy mass - I beat for several minutes on high speed of the mixer.

Add the egg yolks - and mix briefly.

Add the desiccated coconut to the butter and mix briefly.

Add a little flour and milk alternately to the butter.

Mix together, briefly - just until the ingredients combine.

Transfer the batter to the baking pan and bake for 20 minutes.

Lightly beat the egg whites, start adding sugar in portions and beat on high speed of the mixer until the foam becomes very white, shiny and smooth.

Add lemon juice (or vinegar) and potato starch to the egg whites - mix briefly.

Sprinkle in the almond flakes and gently mix.

Arrange the plums densely on the pre-baked base - skin side up.

Spread the meringue over the plums and level it.

Bake the cake for another 35 minutes.

After baking, cool the cake completely before removing it from the pan.