Place a cake board on a clean work surface. Place the cake ring down on top of the cake board and line the inside of the cake ring with acetate, making sure to tape the seam together
Cut a 6-inch circle from your already-made brownies and place it inside the cake ring and acetate. This is your first layer!
Next, layer the softened pint of peanut butter ice cream on top of the brownie, using a bent spoon so you can even out the layer. Freeze after this step for 15 minutes
Spread the Oreo butter on top of the peanut butter ice cream into a thick layer and smooth out the top
In a microwave-safe bowl, combine peanut butter and coconut oil. Microwave in 15-second intervals stirring in between until mixture is completely smooth
Pour peanut butter mixture on top of the oreo layer. Return the cake to the freezer for another 20 minutes until the peanut butter layer is frozen solid.
Top the frozen peanut butter layer with your last pint of ice cream and smooth out the top. Add the crumbled-up oreos ( you can smash these with a rolling pin in a plastic bag) and return the cake to the freezer for at least 3 hours to set.
Let sit at room temperature for 10 minutes before slicing and serving!