Combine ground cookies (ground graham crumb), sugar, ginger, allspice, and cinnamon in a small bowl. Set aside until needed.
Add chopped dried fruits to a small bowl. Cover with rum and set aside over medium heat. Bring to a boil and simmer for 2 - 3 minutes. Remove from the heat and set aside.TipFeel free to substitute the rum with water.
prepare the butter
Add butter to a small saucepan, place over medium heat, and wait for the butter to melt. Remove from the heat and add freshly squeezed mandarin.
prepare fruits and nuts
Peel the apples and pears. Remove the kernels and grate into a large bowl. Add the vanilla sugar, drained dried fruits, and chopped nuts. Stir to combine and set aside. Roughly chop cookies and chocolate.
make the strudel
Take the phyllo sheets from the packaging. Add one sheet on a clean kitchen towel. Place a second sheet of phyllo over the first to overlap for about 10 centimeters or 4 inches. Generously brush the sheet with melted butter and sprinkle half of the pastry with 1/4 of the cookie crumb mixture (step 1) all over the pastry. Arrange 1/4 of prepared fruit on top and sprinkle with 1/4 of chopped cookies and chocolate. Use the rest of the ingredients to make four smaller strudels. Place a rack in the middle of the oven and preheat it to 180 °C / 350 °F. Line a large 25 cm x 30 cm (10-inch x 12-inch) baking sheet with parchment paper.
roll into a strudel
Start rolling the pastry into a strudel on the shorter edge. Roll into a tight strudel. Seal the edges with your fingers to prevent the filling from falling out. Transfer the strudel onto the prepared baking sheet and repeat the process with the rest of the ingredients. Brush the strudels with melted butter before baking.
Place the strudel in the oven and bake for 50 - 60 minutes at 180 °C / 350 °F or until the pastry is golden-brown and crunchy. Leave the baked Christmas strudel on the baking sheet for at least 30 minutes to cool, dust it with powdered sugar, and serve.