Pumpkin chai cake crumb

1. If not using a pre-made chai mix, combine all ingredients together for your homemade chai mix in a mug or small bowl. 
2.  Start making your crumb by preheating the oven temperature to 300°F and lining a quarter sheet pan or baking sheet with parchment paper.
3. In your mixing bowl with the paddle attachment, mix all of the dry ingredients for the crumb (sugars, flour, baking powder, crumbled Biscoff cookies, salt, and chai mix) on low speed until combined. Combine oil and vanilla in a medium container or bowl and stream them into the mixer while paddling on low. 
4. Mix until you see small clusters of your ingredients forming, and use your hands to clump the mixture together and spread out on your baking sheet.
5. Bake crumb for about 20 minutes, or until light golden brown. Let cool completely. 

Pumpkin chai cake sponge

1. Increase the oven’s heat to 325°F, and line a quarter sheet pan with parchment paper on all sides. Butter and flour well or coat it with baking spray before setting aside.
2. To a large mixing bowl, add and whisk together the following dry cake ingredients: all-purpose flour, baking powder, baking soda, kosher salt, and 2 tbsp of your chai spice mix. Set aside.  
3. Using the paddle attachment in the bowl of a stand mixer, cream your butter and sugars together on medium-high for 2-3 minutes. Stop mixer and scrape down the sides of the bowl. Add the egg and canned pumpkin, and mix on medium-high again for 2-3 minutes. You may need to cover your stand mixer with a towel to avoid splatter.   
4. Combine your buttermilk, oil, and vanilla extract together in a measuring cup or small container. Reduce the mixer to low and slowly drizzle that into the bowl. Once all ingredients are incorporated, increase the mixer’s speed to medium-high and beat for 5-6 minutes, until mixture is completely homogeneous with no streaks in the batter. 
5. Incorporate dry ingredients into wet for about 45 seconds with your mixer. Continue incorporating by hand with a spatula until well-combined. Scrape the bowl’s sides to ensure no dry ingredients are hiding in pockets. 
6. Pour and evenly spread the batter into your prepared quarter sheet pan. Bake for 25-30 minutes, rotating halfway through baking. You’ll know your cake is done around the 25-minute mark when it appears buttery and dense but bounces back at the touch of your finger.
7. Transfer to a wire rack to cool completely. 

Mascarpone frosting

1. Chill your stand mixer’s bowl for at least 15 minutes, then, using a whisk attachment, whip your mascarpone on medium speed for  about 1 minute.  
2. Stop mixer to add your powdered sugar and extracts to the bowl. Return your mixer to a low speed and slowly pour in your heavy cream. Once powders and extracts are incorporated, bump up your mixer to medium high speed and continue whipping until all ingredients are combined, about one more minute. Closely watch bowl to avoid over-mixing, as it will cause the frosting to develop lumps and curdle.
3. Transfer frosting to a piping bag fit with a large round tip.

Cake Assembly

1. Use your metal 6-inch cake ring to stamp out two circles from the cake and two smaller half circles. The half-circles will form the bottom layer. 
2. Build your cake on a cake circle OR clean piece of parchment on a baking pan that will fit in your freezer.
3. Line the ring with one 5-6” tall acetate strip. Place cake scraps inside ring and use the back of your hand to press them into a flat, even layer. 
4. If using the milk soak, drizzle half of it onto the bottom layer of your cake, which will quickly absorb it.
5. Pipe roughly ¼ of your frosting on top of the bottom layer and sprinkle about 1/3 of your chai crumb. Again use your hands to gently press the crumb into the frosting so it sticks to it. Add another coat of frosting on top to hold the crumb in place.
6. Repeat steps with next two layers of cake, except skipping the milk soak for the top layer. To create the pumpkin stencil, reserve some frosting for a thin layer for the cake’s top. 
7. Place cake in freezer for a minimum of 3 hours to set the cake and filling. 
8. At least 3 hours ahead of serving the cake, pull it from the freezer and slide off the cake ring. Gently remove acetate and transfer cake to platter or cake stand. Let fully thaw, then serve!

Optional pumpkin stencil:

1. Spread Cool Whip, remaining mascarpone frosting, OR homemade whipped cream on top of your cake. 
2. Cut out a 6” circle on waxed paper, and draw and cut out a pumpkin design within the circle. Place the cutout of your pumpkin atop your cake, and lightly dust the top of your cake with the spice. Remove waxed paper to reveal pumpkin design.