Preheat oven to 350 degrees.

Prepare a round, 9 X 2-inch cake pan by melting the 2 tablespoons of butter in it. Place the butter in the cake pan, and while the oven is warming up, place the pan in it for a couple of minutes. (I like to leave it the oven about 30 seconds or so beyond melting it, to let it bubble and get a little bit brown -- this adds a lovely nutty flavor!)

Remove the pan from the oven and gently tilt it around, coating the bottom and sides with the butter. Then evenly sprinkle in the brown sugar, followed by a layer of the plums. Set aside.

To make the cake batter, use an electric mixer on a high speed to beat the eggs with the sugar until the volume has almost tripled. This will take about 7 minutes. Add the pandan and beat for another few seconds -- until there is a nice light green hue. Now use a large mixing spoon to mix in the almond meal, vanilla, and honey. Once it's nicely combined, fold in the melted butter.

Pour the cake batter directly over the plums in the cake pan and place it in the oven until the cake has solidified -- it should be slightly golden and the center shouldn't jiggle when you gently move the pan. The baking time is approximately 35 minutes.

Let the cake sit for about 10 minutes and then invert it onto a large platter.

In a tiny sauce pan or in a glass bowl for the microwave, heat 1 tablespoon of water with the apricot jam. Mix it with a spoon and then use a pastry brush to lightly coat the top of the plums. This will give the top of the cake an extra sheen. Let the cake sit another 30 minutes before serving.