Melt 3 Tablespoons of butter and set aside to cool slightly. Place 20 oreo cookies (with the filling) in a large plastic bag or in the bowl of your food processor and crush into fine crumbles.
Add the melted butter to the bag and mix it up to coat the cookie crumbs. If using a food processor, you can pour the cookie crumbs into the pie plate and mix the butter in to coat all of the crumbs.
Press the cookie crumbs along the edge of the pie pan to form the crust. If your cookie mixture isn't sticking to the sides, then you need to add a little more melted butter. Only add a Tablespoon at a time because you don't want it to be to wet of a mixture. Once the sides are formed, press the cookie crumbles onto the bottom until you have a crust that covers the entire bottom. Set aside or place in the freezer or refrigerator until ready to fill with the mousse.
Chocolate Mousse Filling
Ninja Foodi Cold & Hot Blender Instructions
In this order, add the ⅔ cup of sugar, ¼ cup of heavy whipping cream, and 2 large eggs to the blender pitcher and select the cocktail function. Check a temperature about 5 minutes into the cycle to make sure it has reached 150℉/66℃. If it hasn't, you can use the manual heating mode on low and pulse every minute or so until the mixture reaches the desired temperature and holds there for 5 minutes. This step is not necessary if using pasteurized eggs, simply make sure the mixture is blended.
Add 7 ounces of dark chocolate and the espresso powder to the blender. The chocolate will start to melt from the residual heat of the egg mixture. You can simply let the chocolate melt by pulsing a few times or select the cocktail function again and let it run for a few minutes until the chocolate is completely melted.
Add the salt, vanilla extract, and room temperature butter and select the smoothie function. When that is done, transfer to a medium size mixing bowl to cool.
Stovetop Instructions
Using a double boiler set up or a heat resistant bowl on top of a saucepan, add a few inches of water in the pan and bring to a boil. Reduce the temperature down to low or medium so the water continues to simmer. Place the double boiler or bowl on top of the pot, making sure the bottom of the bowl does not touch the water.
Add the sugar, heavy cream, and eggs. Whisk constantly until the sugar melts and the temperature of the mixture reaches 150°F/66°C and hold it there for 5 minutes. Don't stop whisking or the eggs could start to cook.
If using pasteurized eggs, you don't have to worry about the temperature, but you do want the sugar to melt so your filling isn't grainy.
Turn the heat off and add in the chocolate and espresso powder. Whisk as the chocolate is melting. When completely melted, remove the bowl from the pot and add in the salt, vanilla extract, and room temperature butter. Whisk to combine. The mixture should be nice and smooth. Set aside to cool while you make the whipped cream.
Whipped Cream for Mousse Filling
You can use a stand mixer, hand electric mixer or do this by hand using a bowl and a whisk.
Add 1 cup of heavy whipping cream to a medium size mixing bowl. Make sure the bowl is clean and dry. Use the whisk attachment on a stand mixer to whisk the whipped cream until soft peaks form. This only takes 3-5 minutes, so watch it carefully. You don't want to over whip it or the cream will be too stiff to incorporate into the chocolate.
The instructions are the same for a hand mixer. To whisk by hand takes a little longer, but certainly can be done.
Mixing the Mousse
Add about 1 cup of the whipping cream to the cooled chocolate mixture and gently fold to incorporate. This will loosen the chocolate and make it easier to combine with the remaining whipped cream. Continue to add the whipped cream and fold into the chocolate mixture or add the chocolate mixture to the whipped cream. Either way works, so do what is easiest for you. I usually add the chocolate to the bowl of whipped cream because I have a handle on the bowl of my stand mixer and it makes it easier to tilt the bowl and fold it all together.
Pour the mousse into the prepared pie crust and smooth the top or make a design on the top if you don't plan on decorating it. Put the pie (uncovered) in the refrigerator for at least 4 hours to set up. You can leave the pie in the refrigerator for several days, so it's a great make ahead pie.
Decorating
When the pie is chilled and set, you can decorate it or eat it now.
Whip up 1 cup of heavy whipping cream using a stand mixer or electric hand mixer on low (or whisk by hand) until the mixture starts to thicken. Add in the powdered sugar and vanilla extract and mix for 30 seconds on low or medium speed.
Turn the mixer to high speed (or whisk by hand) until the cream thickens and holds its shape. If you are spreading the whipped cream over the top, take the cream to the point where it forms soft peaks. If using a pastry bag with a tip for decorating, whip it a little longer so the decorations hold their shape.
Spread or pipe the decorations you want on your pie and top with chocolate shavings or crushed chocolate tips. For detailed instructions on how I decorated my pie, see the written post.
If you put the pie back in the refrigerator for at least 1 hour, it does make it easier to slice. I can never wait, so I slice and serve right away!
The nutritional information is based on 8 servings per pie, however I cut mine into 12 smaller pieces because it is a very rich pie.If using Cool Whip in the filling use 2 cups. Nutritional values are provided as a courtesy and thesaltedpepper.com makes no guarantees of accuracy. We do our best to ensure they are accurate, but many factors influence nutritional values that are beyond our control. Different brands of items have different nutritional values, so it is always best to do your own independent nutritional analysis based on the items you are using in a recipe if you require a high level of accuracy. Thesaltedpepper.com will not be held accountable for any errors in the displayed nutritional information.