01 -
Warm your oven to 325ºF (163ºC). Crush 16 chocolate sandwich cookies in a food processor till you get fine crumbs. Mix in 4 tablespoons melted butter and blend well. Push the mix into a 9-inch pie dish. Pop it in the oven for 15 minutes until it smells good, then let it cool on a rack.
02 -
Grab a microwave-safe container and put in 4 ounces dark chocolate, 3 tablespoons butter, 3 tablespoons cooking oil, and 1 1/2 tablespoons cocoa. Microwave at half power, giving it a stir now and then, until everything's melted (around 90 seconds). In a separate bowl, mix 2/3 cup dark brown sugar, 2 eggs, 2 teaspoons vanilla, and 1/4 teaspoon salt. Dump the chocolate mix into the wet stuff, then gently add 3 tablespoons of plain flour. Pour over the cookie base and bake for 15 minutes until the edges firm up. Let it cool for an hour on a rack, then stick it in the fridge for another hour.
03 -
Set oven to 325ºF (163ºC). Put parchment on a baking tray. Break up 6 chocolate sandwich cookies into small chunks. Mix 2 tablespoons icing sugar, 1 tablespoon cocoa, 1/8 teaspoon salt, and 2 tablespoons melted butter with the broken cookies. Spread it all on the tray and bake for 10 minutes, giving it a stir halfway, until it smells good and gets crunchy. Cool it on a rack.
04 -
Put 6 ounces milk chocolate in a microwave-safe bowl and melt at half power, stirring often, until smooth (90-120 seconds). Warm 3 tablespoons heavy cream in the microwave (15 seconds) till it reaches 105º-110ºF and mix with 2 tablespoons cocoa. Add 2 tablespoons icing sugar, a tiny bit of salt, and the rest of the cream (about 13 tablespoons). Beat using a stand mixer until soft peaks show up (roughly 2-3 minutes). Mix 1/3 of the whipped cream into the melted chocolate. Then carefully fold in what's left. Spread this mousse on top of the cooled brownie part.
05 -
Sprinkle the cookie crumb mix on top of the pie. Put it in the fridge for 3-4 hours or leave it overnight before you serve it.