Oatmeal chocolate chip cake layers baked on a Biscoff cookie crust with Biscoff spread and buttercream.
Preheat your oven to 375 degrees F. Spray three 8-inch or four 6-inch round cake pans with non-stick spray and then line with parchment. Spray again. Set aside.
In a medium sized bowl combine the Biscoff cookie crumbs, melted butter and sugar. Stir until all the crumbs are damped by the melted butter. Alternatively, you can add the melted butter and sugar to your food processor after you've pulverized the cookies.
Divide evenly between the three pans or four pans (4oz. in 8" pans and 3 oz. each in the 6' pans) and press down firmly with your hand or the back of a measuring cup.
Bake for 5 to 7 minutes, until golden brown. Let cool while you make the cake batter.
Preheat your oven to 325 degrees F.
In a medium sized mixing bowl, whisk together the flour, finely ground oats, cinnamon, baking powder and salt. Set aside.
In the bowl of an electric mixer, fitted with the paddle attachment, cream the butter and the sugar for two minutes on medium-high speed.
Scrape down the sides of the bowl and begin to add the eggs on medium speed, scraping down the sides and bottom of the bowl between addition. Stir in the vanilla.
With the mixer on low speed, add 1/3 of the flour mixture, followed by 1/2 of the milk. Repeat the additions, 1/3 cup flour mixture, 1/2 milk and the final 1/3 cup flour mixture. Only mix until the flour mixture is incorporated, about 30 seconds. Scrape down the sides and bottom of the bowl and mix again for another 20 to 30 seconds on low.
Toss the chocolate chips in one tablespoon flour and then fold the chocolate chips into the cake.
Evenly divide the cake batter between the three 8-inch pans or the four 6-inch pans (20 oz. in each 8" pans and 15 oz. in each 6" pan). Bake the cake layers (either size) at 325 for 28 minutes or until a toothpick inserted in the center of the cake comes out with a few moist crumbs on it.
Let cool for about 15 minutes in the pans before inverting onto a wire rack to cool completely.
Once cooled completely, each layer can be wrapped in plastic wrap and stored in the freezer for up to a week. For longer storing, also wrap in foil.
In the bowl of electric mixer fitted with the paddle attachment, combine the butter and Biscoff spread. Beat on medium-high speed until smooth, about 45 seconds.
Add the powdered sugar to the bowl and mix in, slowly at first until incorporated, then increasing the mixer speed to high. Blend in the vanilla extract, salt and heavy whipping cream, and continue to whip on high speed until very fluffy, about 4-5 minutes, scraping down the sides of the bowl as needed.
Beat frosting by hand with a wooden spoon to get air bubbles out.
Place the first layer on your cake plate or cake stand (see above tutorial) and cover with about 3/4 cup Biscoff spread.
Place the second layer on top and evenly spread more Biscoff on top.
Place the final cake layer, also top-side up, on the filling and cover the cake with a thin layer of the Biscoff buttercream. This is the crumb coat. Freeze the crumb coated cake for 10 minutes in the freezer.
Continue frosting the cake with the Biscoff buttercream. (Tutorial above)