Preheat the oven to 350 degrees Fahrenheit. Grease two 8 inch cake pans with vegetable oil, line with parchment paper and then lightly grease again with vegetable oil.
Make the ganache first: Place the chocolate chips and the butter/vegan baking sticks in a microwave safe bowl. Heat in 10 second increments, stirring after each time, until the melted, incorporated and silky smooth.
First let the ganache sit on the counter until it has cooled a bit, whisking every now and then. Then refrigerate until spreadable. If it gets too hard when ready to use, microwave again in 5 second increments until you get the spreadable texture.
Place the 10 gluten free chocolate sandwich cookies in a zip top bag. Seal the bag. Using a rolling pin or the flat side of a meat mallet, smash the cookies into a sand like consistency. Set aside.
In a large bowl whisk together the gluten free flour, sugar, baking soda, salt and cocoa powder.
Add in the cookie crumbs and whisk to incorporate.
Make 3 wells in the dry ingredients.
In the first well, pour the vegetable oil.
In the second well, pour the white vinegar.
In the third well, pour the vanilla.
Pour the cold water over everything and whisk together until just combined. If it starts getting thick, use a spatula instead of a whisk.
Divide the batter evenly between the two 8 inch pans and smooth the tops with a butter knife.
Bake in the center rack of the oven for 50 minutes.
Remove from the oven and let cakes cool completely in pans. Once cool, remove from pans and transfer to a cooling rack. Slice the two cakes in half horizontally, now you will have 4 thin layers of cake.
Make the vanilla frosting: In a large bowl of an electric mixer or using a hand held mixer, beat the softened butter/vegan baking stick until smooth and creamy. About 2 minutes.
Add in the confectioners’ sugar, water and vanilla and beat till combined and smooth and creamy. Set aside.
Make the cookies and cream buttercream: In a large bowl of an electric mixer or using a hand held mixer, beat the softened butter/vegan baking stick until smooth and creamy. About 2 minutes.
Add in the confectioners’ sugar, water and vanilla and beat till combined and smooth and creamy.
Break about 7 chocolate sandwich cookies into the buttercream. You want chunks of cookies.
Gently fold the cookies into the buttercream using a spatula.
Divide frosting into 4 equal servings.
Assemble the cake: Place one layer of cake on the cake stand. Take ¼ of the cookies & cream buttercream and frost the top.
Place the vanilla frosting (not the cookies and cream frosting) in a piping bag or a zip top bag with the corner cut off. Pipe a ring around the top edge of the cake. If you try this with the cookies & cream frosting the cookie chunks will get stuck and burst open your piping bag.
Spoon 3-4 tablespoons of the thick ganache into the middle of the ring of frosting.
Sprinkle chunks of broken chocolate sandwich cookies on top of the wet ganache and gently press in to make sure they stick. I use 3 broken cookies per layer.
Place another layer of cake on top and repeat. Do this process 3 times.
Frost a thin layer of frosting on the top of the cake and sides of the cake. Use a cake scraper or a icing spatula to scrape excess frosting off the sides of the cake. This should be a semi naked cake. Pop the cake in the fridge uncovered for 15 min to harden. If you’re running out of frosting, you can always use a little of the regular vanilla.
Make the ganache liquid again: Microwave ganache in 5 second increments until it is very melted and pourable.
Take the cake out of the fridge. Spoon about 9 tablespoons of the liquid ganache on top of the cake. Take an icing spatula and push the ganache around to the edges of the cake so it drips down the sides. Work quickly since the cold cake will harden the ganache fast.
If desired, put the rest of the vanilla frosting into a piping bag and pipe swirls or dollops all around the edge of the top of the cake. Shove on some chocolate sandwich cookies halves. Pop in the fridge, uncovered, to let ganache harden for about 15 min.
Store cake in the fridge under a dome or wrapped in foil until ready to serve. When ready to serve, let the cake sit out for about 20 min prior to cutting. Wrap any extra slices in foil and store in the fridge. Enjoy!
Video
Notes
You'll need 34 chocolate sandwich cookies to make this cake. You could use less, I won't judge you.