Preheat the broiler grill on the oven and set the top rack so it is about 7 inches from the top element. Prepare one 9-inch (23 cm) springform pan or two 8-inch (20 cm) springform pans by greasing them and lining the bottom with a circle of parchment paper cut to fit.

In the medium bowl, cream the almond paste, diced, (or almond flour, honey, and almond flavour) with the butter using an electric mixer until they are smooth and fluffy.

Separate the eggs, putting the yolks into a spouted measuring cup or a small bowl and the whites into a large mixing bowl.

Keep beating the almond paste and butter and slip in one yolk at a time from the cup or bowl they are in, beating after adding each yolk. Add the rum, vanilla, and salt, and beat well. Set aside.

Using clean beaters, beat the egg whites in the large bowl until soft peaks form. Add the sugar gradually. Keep beating the egg whites until they are thick and glossy.

Scoop out about ¼ of the beaten whites and stir them into the yolk mixture until they are incorporated, but not deflated.

Sift together the flour and cornstarch into a small bowl.

Add one third of the tempered egg yolk mixture to the beaten egg whites in the large bowl and sprinkle with one third of the flour mixture. Use a silicone spatula to fold them gently together. Repeat two more times until the flour and yolks are just incorporated.

If you are using apricot jam between the layers, heat ½ cup of the apricot jam until it's melted and have it ready.

Plop a heaped half-cup of batter into the prepared pan. Smooth the batter into a thin, even layer. Place the baking pan on the rack under the broiler and grill just until the top is a nice dark golden brown.

Remove the pan from the oven and add another layer of batter. Broil it again, watching it closely.

Keep spreading and broiling layers, brushing on a thin layer of jam under the batter about every third layer.

When you've completed the last layer, set the cakes aside to cool completely. Remove the cake pan sides.

To glaze the cake: Heat the remaining ½ cup of apricot jam and brush a layer of jam all over the top and sides of the Baumkuchen.

In a small saucepan heat the chocolate, cream, coconut oil, and rum over low heat until melted and smooth.

Pour the glaze in a puddle on the top of the cake, then use a spatula to gently work small amounts to the edge of the cake so they drape down the sides.

Let the glaze set, then use two flat pancake flippers to carefully slide the cake off the base and onto a serving plate.