Step 1

Preheat your oven to 325 degrees F. Spray three 8-inch pans with non-stick cooking spray, line the bottoms with parchment and spray again. Set aside.

Step 2

Place the Biscoff cookies in a food processor or blender and pulse until the cookies are finely ground and resemble flour.

Step 3

In a medium-size bowl, combine the Biscoff crumbs, all-purpose flour, baking powder, baking soda, and salt. Whisk until the ingredients are well-blended. Set aside.

Step 4

In the bowl of a stand mixer fitted the paddle attachment, beat the butter and sugars on medium speed until light and fluffy. Add the eggs, one at a time, beating well after each addition.

Step 5

With the mixer on low speed, add 1/3 of the dry ingredients and mix until combined. Slowly add half of the buttermilk and mix until incorporated. Continue alternating the flour and buttermilk until it has all been incorporated. Scrape down the sides of the bowl and slowly mix for another 20-30 seconds.

Step 6

Divide the batter evenly among your pans and bake for about 30 to 35 minutes. Cool 10 minutes on a wire rack before inverting onto cooling racks to cool completely.

Step 7

Preheat your oven to 375 degrees F. Line a baking sheet with parchment paper and set aside.

Step 8

In a food process or blender, pulse all of the ingredients (except for the butter) a few times. We just want to break up the cookies and nuts a bit. This doesn’t need to be as fine of a consistency as you use in the cake layers.

Step 9

Add the butter and pulse a few more times to create clusters. Spread the crumble over the parchment paper and bake for 8 to 10 minutes, stirring the mixture to break it up halfway through. Let it cool completely and then crumble the mixture into smaller pieces, if needed.

Step 10

In a chilled stainless steel bowl, beat the heavy whipping cream until stiff peaks form. Set aside.

Step 11

In a medium size mixing bowl, beat the cream cheese and powdered sugar until smooth, about 2 minutes.

Step 12

Add the pumpkin puree, vanilla, brown sugar, and pumpkin pie spice. Mix until smooth.

Step 13

Fold in the heavy whipping cream into the cream cheese mixture.

Step 14

Store in an airtight container in the refrigerator until ready to use.

Step 15

Combine the pecans and oil in a food processor and blend until you've created a nut butter.

Step 16

In an electric mixer fitted with the paddle attachment, beat the butter on medium-high speed for about 2 minutes.

Step 17

With the mixer on low speed, add the pecan butter and Biscoff cookie butter. Mix until well combined and smooth.Gradually add the powdered sugar.

Step 18

Turn the mixer to medium-high speed and beat the buttercream for about 3 to 5 minutes.

Step 19

Before spreading on your cake, spend a couple minutes mixing the buttercream by hand with a wooden spoon to push out the air pockets.

Step 20

Divide each cake layer in two, horizontally, using a cake leveler or serrated knife. You should have six thin cake layers.

Step 21

Place a dollop of frosting on the cake board or cake plate. Place the first cake layer, top-side up, on the cake board or cake stand.

Step 22

Spread about 1/2 cup of buttercream across the cake layer, leaving about an inch clear around the edge of the cake.

Step 23

Pipe buttercream dollops around the entire edge of the cake, using the Wilton 8B tip.

Step 24

Fill the center with about a half cup of the pumpkin cheesecake filling.

Step 25

Sprinkle 1/3 cup of the Biscoff crumble on top and pat into place.

Step 26

Place the second cake layer on top of the filling and repeat these steps with the remaining 5 layers of cake.

Step 27

Place the final cake layer, top side down, on the filling.

Step 28

Decorate the top of the cake using the remaining buttercream and crumble.

Step 29

Place a dollop of frosting on the cake board or cake plate. Place the first cake layer, top-side up, on the cake board or cake stand.

Step 30

Spread about 1/2 cup of buttercream across the cake layer. Pipe a rim of buttercream around the edge of the cake.

Step 31

Fill the center with a generous cup of the pumpkin cheesecake filling.

Step 32

Sprinkle a half cup of the crumble on top and pat into place.

Step 33

Place the second cake layer on top of the filling and repeat these steps.

Step 34

Place the final cake layer, top side down, on the second layer of filling.

Step 35

Apply a thin coat of buttercream around the entire cake. This is the crumb coat. Freeze the cake at this stage for 15 minutes to set the crumb coat and lock the crumbs into place.

Step 36

After the crumb coat is set, finish frosting the cake with the remaining buttercream, and decorate with crumble.