Marzipan gets mixed into the cake batter to create a light, almond flavor base for pounds of Apricots! Sweet, but not too sweet, and a hint of tart from the fruits. Make the cake with fresh apricots in season, or used canned ones to brighten up a day any other time of the year.
Beat the Butter and Marzipan in a mixer until they come together, 4-5 minutes. I find this is easier with the whisk attachment. It should become mostly smooth, and it is ok if you still see small bits of marzipan.
Switch to a regular beater attachment for the mixer. Slowly add the sugar, vanilla sugar, and almond extract. Beat until the mass comes together.Add egg yolks one at a time. Beat for 20 to 30 seconds after each addition.
Combine the flour, salt, and baking powder. With the mixer running, slowly add the dry ingredients to the butter/sugar/marzipan mixture.
Whip the egg whites to a soft peak.Fold the beaten egg white into the mixture a little at a time. You want it completely incorporated, but you don't want to smash out all of the lift from the egg white.
Spread the batter into your prepared pan.
Top the batter with apricot halves. Make circles, layering them a bit.
Sprinkle with sliced almonds, if you like.
Bake 45 minutes.
Warm apricot jam, and mix with water. If your jam has fruit "bits", pour it through a strainer to make it smooth. Brush the hot cake with warm apricot jam.Let the cake cool completely before serving.
Notes
I got into the habit of whipping egg whites first, and setting them aside in another bowl... this way I don't have to clean the mixing bowl for the egg whites after making the batter. Even better, now I have a hand mixer and an extra bowl. It may feel frustrating trying to get the marzipan to whip into the butter. Pinch off little pieces to add to the butter, then whip. It can take a few minutes. A few little lumps won't hurt, and should smooth out by the time you put in the flour.