Place all ingredients aside from the dissolved cornstarch into a pot. Simmer over a low to medium flame until apples are tender, brown, and caramelized, about 45 minutes to an hour.

Add dissolved cornstarch and cook an additional two to three minutes or until slightly thickened.

Allow to cool to room temperature before assembling the tiramisu.

Place nine to 10 ladyfingers horizontally in a three-pound or 10- by four-inch (1.36 kilogram or 25- by 10-centimeter) loaf pan, sugar side up.

Spread about 1/3 cup of custard gently on top. Spread half the apple filling on top of the custard. Repeat with another layer of ladyfingers, custard, and apple filling. Place a third layer of ladyfingers on top of the apple filling and top with another slightly thinner layer of custard, leaving some extra aside for piping.

Place remaining custard into a piping bag and pipe any decorative design of your choice on top of the tiramisu.

Tent two layers of aluminum foil over the pan so as not to get custard on the foil, and cover tightly. Refrigerate for at least eight hours before serving so the ladyfingers have time to soften.