Step 1: Prepare the gingerbread cake according to your favorite recipe and allow it to cool completely before cutting into 1-inch cubes.
Step 2: In a medium saucepan, combine water, sugar, cinnamon stick, and grated ginger to create the poaching liquid for your pear gingerbread trifle recipe.
Step 3: Add the sliced pears to the liquid and simmer over medium heat for 15-20 minutes until tender but firm.
Step 4: Remove pears from the liquid and continue to boil the syrup until it reduces by half, then let it cool.
Step 5: Whip the heavy cream with powdered sugar and vanilla extract until stiff peaks form.
Step 6: In a large glass trifle bowl, place a layer of gingerbread cubes at the bottom and drizzle with some of the reduced pear syrup.
Step 7: Add a layer of vanilla custard, followed by a layer of the poached pears.
Step 8: Repeat the layers until the bowl is full, finishing with a thick layer of whipped cream on top.
Step 9: Chill the pear gingerbread trifle recipe in the refrigerator for at least 4 hours before serving, garnishing with crystallized ginger just before presenting.