This chocolate mousse pie is by far one of the best desserts I have ever made, and I don't say that lightly. It is incredibly rich and decadent with an Oreo crust, creamy chocolate mousse filling, and a smooth chocolate ganache. It is a chocolate lovers dream!

Why you will love this chocolate mousse pie
- The Oreo crust. I was debating whether I should make this pie with a graham cracker or Oreo crust, and ultimately went Oreo. How better to top off a decadent dessert than with a rich, buttery, Oreo crust?
- The chocolate mousse filling. My favorite part of the pie! I can eat this chocolate mousse with a spoon (and I have). It is so smooth and creamy. Mousse looks impressive but it actually is really easy to make and has very simple ingredients.
- The chocolate ganache. This pie is finished off with a chocolate ganache. We have a layer of chocolate ganache on top of the mousse and then a whipped chocolate ganache piped on top.

Key ingredients
- Oreos: Oreo cookies are used for the crust. They are pulsed down to a fine crumb in a food processor, then mixed with a little butter, and packed into the bottom of your pan.
- Butter: salted butter is used in this recipe for the crust - it offsets the sweetness of this dessert perfectly.
- Egg yolks: egg yolks are needed to thicken the mousse mixture and bind all the ingredients together.
- Granulated sugar: granulated sugar is the sugar of choice to sweeten up the filling a bit.
- Heavy whipping cream: we use a lot of heavy cream in this recipe, so make sure to splurge on the good quality stuff!
- Semi-sweet chocolate: the star ingredient! We use a total of 16 oz of semi-sweet chocolate in this recipe, so make sure to use good quality chocolate. Chocolate chips don't melt as easily as chocolate bars, so chocolate bars are ideal here. I like to use Ghirardelli 4 oz semi-sweet chocolate bars!

Steps
- Make the Oreo crust. Pulse the Oreos into a fine crumb in a food processor and mix with the melted butter. Pack into your pan and pre-bake for 10 minutes at 350F. Let cool completely.
- Make the mousse. Whisk together the egg yolks, sugar, and salt in a heat proof bowl. Place the bowl over a sauce pan with 2 inches of simmering water and heat for about 5 minutes. Add in the warm heavy cream and mix for 2 minutes. Remove from the heat and stir in the vanilla extract. Then add the melted chocolate and mix until combined. Fold this mixture into the whipped heavy cream. Set aside.
- Assemble. Pour the mousse on top of the cooled Oreo crust and chill for 3 hours.
- Make the ganache. Chop your chocolate and pour hot heavy cream on top. Let it sit for 5 minutes, then stir until smooth. Pour ⅓ of the ganache on top of the chilled pie. Put the pie and the other ⅔ of the heavy cream back in the fridge for 45 minutes.
- Whip the ganache. Beat the set aside ganache until fluffy. Pipe on top of the pie. Enjoy!

FAQ
Why is my crust so hard?
A crust that is hard is due to over baking. The Oreo crust only needs to be baked for 8-10 minutes until aromatic. Any longer and it will be hard and burnt.
Why is my chocolate mousse soupy?
A soupy chocolate mousse can be from two things. One - you can over mix the chocolate mousse mixture. After you add the eggs/chocolate mixture to your whipped cream, make sure to only fold until JUST combined, otherwise the whipped cream can deflate.
Two - if you pour the chocolate mousse mixture into a warm crust, the crust will heat the mousse and it will turn soupy. Make sure the crust is completely cold. I like to put it in the freezer for 10 minutes prior to filling it.
Why is my chocolate ganache lumpy?
Lumpy chocolate ganache is likely from the heavy cream not being hot enough. The hot cream sitting over the chopped chocolate is supposed to melt it. If it doesn't, it probably wasn't heated for long enough.
If you find that your chocolate ganache is lumpy, microwave the ganache in 10-15 second increments, stirring between each. This should melt the chocolate and smooth out the mixture.

How do I get clean cuts?
The way to get smooth clean cuts for impressive looking slices is to run your knife under hot water and wipe dry before cutting. The warm knife will slice cleanly through the pie. Rinse and repeat in between cutting each slice.
How do I store this pie?
Store the pie in an air tight container in the fridge. It should stay fresh for 3-4 days.
What type of pan should I use?
I baked this pie in an 8 inch springform pan - you don't need to do this, it just makes the pie easier to remove once you are finished. Although, you can bake this in a regular cake or deep dish pie pan if you desire!

Baking in grams
While I provide volume measurements for the recipes on my blog, I highly suggest baking these recipes using weight. It is the most standardized and accurate way to bake. I carefully recipe test all of my recipes using a kitchen scale, not by using cups, and therefore I cannot guarantee the success of my recipes when using volume measurements.
Other pie recipes you may like
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Chocolate Mousse Pie
Equipment
Ingredients
Oreo Crust
- 22 regular Oreos
- 5 tablespoons (71 grams) salted butter melted
Chocolate Mousse
- 4 egg yolks
- ¼ cup (50 grams) granulated sugar
- ¼ teaspoon salt
- 2 cups (480 mL) heavy whipping cream divided
- ¾ teaspoon vanilla extract
- 2 4 oz semi-sweet chocolate bars chopped
Chocolate Ganache
- 1 cup (240 mL) heavy whipping cream
- 2 4 oz semi-sweet chocolate bars chopped
Instructions
Oreo Crust
- Preheat oven to 350F and line the bottom of an 8 or 9 inch springform pan with parchment paper. You don’t have to use a springform pan, it just makes it easier to remove the pie once it is finished. Set aside.
- In a food processor, pulse the Oreos until they are a fine crumb. Add the melted butter and pulse until combined. If you don’t have a food processor, put the Oreos in a ziplock bag and gently hit them with the back of a wooden spoon/spatula. Then mix them with the butter in a bowl.
- Pack the Oreo mixture into the bottom and up the sides of the prepared pan. Using the back of a measuring cup, press the mixture into the pan to make sure it is secure. The more firmly packed it is, the less likely it will fall apart when cutting it.
- Pre-bake the crust for 8-10 minutes until aromatic. Remove from the oven and let it cool for 10 minutes at room temperature, then place it in the freezer to completely cool. The crust should have absolutely no heat when the filling is poured in.
Chocolate Mousse
- Pour 2 cups (480 mL) of heavy whipping cream into a measuring cup. Pour ¾ cup (180 mL) of that 2 cups into a separate cup/bowl, and put the 1 ¼ cups (300 mL) of heavy cream back into the fridge. You will use this later.
- Chop your chocolate and set aside.
- Fill a sauce pan with two inches of water and bring to a simmer over medium heat.
- In a medium-sized heat proof bowl, whisk together the egg yolks, granulated sugar, and salt until smooth. Place the bowl on the pot over the simmering water and continuously whisk while the mixture heats up. It should get to about 160F, although you don’t actually need to use a thermometer if you don’t have one. This should take about 4 minutes on medium heat.
- Meanwhile, microwave the ¾ cup (180 mL) of heavy cream that you set aside for 45 seconds. It should be luke warm. While continuously whisking the egg mixture, slowly pour the warmed heavy cream into the eggs. Keep whisking the mixture for another 2 minutes. Remove the bowl from on top of the saucepan, add the vanilla extract, and stir to combine.
- Add the chopped chocolate to a microwave safe bowl and microwave it in 30 second increments, stirring in between each increment until completely melted and smooth. You can also do this over the stove using a double boiler.
- Add the melted chocolate to the egg mixture and whisk until completely combined. Set aside.
- Remove the 1 ¼ cups (300 mL) of heavy cream you put in the fridge and pour it into the bowl of a stand mixer fitted with the whisk attachment or a large bowl if using a handheld mixer. Beat the heavy cream on medium speed for 3-4 minutes until medium peaks form. Medium peaks are in between soft peaks and stiff peaks - so not fully formed into whipped cream yet, but not super soft either.
- Pour the chocolate/egg mixture into the whipped cream and fold them together using a rubber spatula until combined. Avoid over mixing, as the whipped cream can lose all the air you just whipped into it and deflate.
- Pour the filling on top of the cold Oreo crust, and place the pan back in the fridge for 3 hours or until set. It normally looks set sooner than 3 hours, but I like to do at least 3 hours just to be safe.
Chocolate Ganache
- After the three hours, make your chocolate ganache.
- Chop your chocolate finely and set aside. Heat the heavy cream until it is hot, about 30 seconds to 1 minute in the microwave. You can also do this on the stove.
- Pour the heavy cream over the chopped chocolate and let it stand for 5 minutes. The hot cream will melt the chocolate. After 5 minutes, stir together until combined.
- Remove about ⅔ of the ganache mixture and put it in a separate bowl and in the fridge. This will be used later to pipe on the pie.
- Pour the remaining ⅓ of ganache over the chocolate mousse and spread into an even layer. Put the pie back in the fridge to set for about 45 minutes.
- After the 45 minutes, carefully remove the sides of the springform pan from the pie (if using one).
- Then, beat the set aside ganache in the bowl of a stand mixer using the paddle attachment, or a medium-sized bowl if using a handheld mixer, until fluffy. Using a piping bag with a star tip, pipe the ganache onto the pie. Top with chocolate sprinkles or chocolate shavings and enjoy!
Tried this recipe? Make sure to rate and review and tag @sturbridgebakery on Instagram!
Donna
So decadent!
Can’t wait to try!
Jess Italiano
Thank you!! 🙂 I hope you enjoy!
Kate
Hello - do you use the whole Oreo or scrape off the frosting prior to food processor?
Jess Italiano
Hi Kate! The whole Oreo!
Kate
Wonderful- going to make tomorrow!
Jess Italiano
Let me know how it turns out!
Kim B
It didn't set. When I took off the spring form pan, it was still very liquid after refrigerating overnight. I'm thinking that I did not whip the cream enough before adding chocolate. The flavor was delicious so I'm definitely going to try again.
Jess Italiano
I am sorry to hear it didn't set, but so happy you're willing to try again! It could definitely be that you didn't whip the cream enough, or it could be from over-mixing after adding the chocolate/egg mixture. Too much mixing and the air you created when you whipped the cream can knock right out of the batter and cause it to deflate.