Slice the vanilla pod in half and srape out the seeds with a knife.
Add the vegan cream cheese, vegan yogurt, Biscoff spread, vanilla, and lemon zest to a high-speed blender or food processor and blend for a minute or two until smooth and creamy.
Mix together the espresso and Amaretto (if using) in a medium bowl.
Assembling the tiramisu
Take enough Biscoff cookies to create 2 layers in the base of an 8x8" dish. Dip one side of each cookie in the espresso soak and arrange them in the base of the dish in 2 layers. A quick dip on one side of each cookie is enough, as you want to avoid letting them soak as they will become too soggy.
Spread about ⅓ of the mascarpone on top of the first 2 layers of cookies. Repeat with another 2 layers of espresso-soaked cookies and another ⅓ of the mascarpone mixture. Finally, repeat with another 2 layers of espresso-soaked cookies and the last ⅓ of mascarpone.
Cover the tiramisu and refrigerate for 4 hours (or overnight if preferred).
Before serving, crush some more Biscoff cookies and crumble them over the top of the tiramisu.
How to store
Cover the tiramisu and keep it refrigerated until ready to serve. It's best when served within 1-2 days. I don't recommend freezing this Biscoff tiramisu.