Preheat your oven to 325°F (165°C). Grease and line the bottom of an 8-inch round cake pan with parchment paper. Sprinkle the crushed Biscoff cookies evenly over the bottom of the pan.
In a medium bowl, whisk together flour, allspice, cinnamon, cloves, ginger, nutmeg, baking powder, baking soda, and salt until well combined. Set aside.
In a large mixing bowl, whisk together the canola oil and brown sugar until smooth. Add eggs, sour cream, and vanilla extract, mixing until everything is well incorporated.
Fold in the grated carrot until evenly distributed.
Gradually add the dry ingredients into the wet mixture, folding until just combined. Avoid overmixing to keep the cake tender.
Pour the batter over the crushed cookies in the prepared cake pan. Smooth the top and bake for 36-40 minutes or until a toothpick inserted into the center comes out clean.
Allow the cake to cool in the pan for about 10 minutes, then turn it out onto a wire rack to cool completely.