Place the sliced apples in a microwave safe shallow bowl. Microwave them in 1 minute intervals until softened and pliable, about 3 minutes. Stir the apples in between intervals. Toss with lemon juice and spiced rum and set aside until cool, about 10 minutes.

Preheat the oven to 325°F. Butter a 9 inch springform pan and place it on a baking sheet lined with parchment or a silicone mat.

In a medium bowl, whisk together 1 cup of flour, 1 cup sugar, baking powder, and salt.

In a large bowl, mix together the whole egg, milk, oil, and vanilla extract/paste. Gradually add in the dry ingredients until just moistened. Remove 1 cup of batter and reserve.

To the remaining batter, whisk in the 2 egg yolks, then fold in the cooled apple slices until they are all coated with batter. Pour the apple mixture into the prepared pan and gently press the apples down to make an even layer.

Add the remaining 2 tablespoons of flour to the reserved batter and whisk until smooth. Spoon on top of the apple mixture and spread evenly to the edges of the pan. Sprinkle the remaining 1 tablespoon of sugar evenly over top.

Place in the preheated oven and bake for 1 hour to 1 hour 15 minutes until golden brown.

Let cool on a wire rack and remove from the pan after completely cooled. Dust with powdered sugar before serving.

In a small saucepan over medium heat, combine milk, maple syrup, and thinly sliced ginger. Bring to a simmer and remove from heat, letting steep for 30 minutes.

After steeping, sieve out the ginger pieces and return to medium heat, bringing the milk back up to a simmer.

In a small bowl, whisk together egg yolks. Slowly mix in a bit of the warm milk mixture to temper the eggs. Then add the yolks and milk mixture to the remaining milk. Stirring constantly, cook the custard until it coats the back of the spoon. Remove from heat and add vanilla and spiced rum.

Pour into a heat safe bowl and let cool on the counter, then refrigerate until cold.