
Dive into these layered chocolate treats that'll satisfy any sweet tooth. They combine a crunchy Oreo base with gooey brownies, smooth chocolate mousse, and fluffy whipped cream on top - making them an absolute dream for chocolate fans.
I've made these countless times and found that letting each layer cool properly is the key to getting all the textures just right.
Key Components
- For Crust:
- Oreo Cookies: Crushed into tiny bits (30)
- Unsalted Butter: Melted
- Reserved Crumbs: Set aside for garnish
- For Brownie Layer:
- All-Purpose Flour: Make sure to measure it right
- Unsweetened Cocoa: Standard type works best
- Large Eggs: Take them out early
- Unsalted Butter: Softened
- Pure Vanilla Extract: Get a good one
- For Mousse and Topping:
- Instant Chocolate Pudding: 3.9 oz box
- Whole Milk: Gives the best flavor
- Whipped Topping: You'll use this twice
- Hot Fudge Sauce: Not heated
Step-by-Step Walkthrough
- 1. Crust Preparation:
- Heat your oven to 350°F. Give your 9x13 pan a good spray. Blitz the Oreos until they're powder. Keep ¼ cup for later. Mix the rest with melted butter and push into the pan.
- 2. Brownie Layer:
- Mix flour, cocoa, baking powder and salt together. In another bowl, whip eggs, sugar, butter and vanilla until puffy. Gently mix in the dry stuff until just combined. Spread on your crust. Bake 25-30 minutes until almost done - you want a toothpick to come out with a tiny bit of batter.
- 3. Mousse Creation:
- Mix milk, pudding mix and powdered sugar for about 2 minutes until it starts setting. Fold in half the whipped topping carefully. Spread this over completely cooled brownies.
- 4. Final Assembly:
- Let it cool in the fridge for 1-1½ hours until firm. Drizzle room temp fudge sauce over top. Add the remaining whipped topping and sprinkle with saved Oreo bits.
- 5. Setting Time:
- Keep it in the fridge at least 2 hours or overnight. This waiting time really lets the flavors blend together.

Keeping and Serving Tips
Keep them wrapped up in the fridge for up to 4 days. For nice clean slices, warm your knife in hot water and wipe it between cuts. You can freeze them up to 3 months - just thaw in the fridge overnight.
Goes Great With
- A glass of milk
- Steaming coffee
- Vanilla ice cream
- Fresh raspberries
- Mint chocolate chip ice cream
- Hot chocolate
Mix It Up
Try these tasty twists:
- Try graham crackers for the crust
- Add peanut butter to the mousse
- Add white chocolate on top
- Mix in mint chips
- Pour on some caramel
- Sprinkle with candy pieces

Closing Thoughts
Getting these bars right comes down to patience with cooling and watching temperatures. Make sure each layer sets up nicely before adding the next one, and you'll get that amazing chocolate experience.
Frequently Asked Questions
- → Can I make these in advance?
- Absolutely, keep them in the fridge for up to two days.
- → Why do I need to cool the brownies?
- Warm brownies mess up the mousse by making it runny. Let them cool.
- → Are these bars freezer-friendly?
- Yep! Freeze them for three months and thaw in the fridge overnight.
- → Can I swap in fresh whipped cream?
- Sure, homemade whipped cream works perfectly for the topping.
- → What’s the trick to cutting clean slices?
- Heat a sharp knife in warm water, dry it off, and repeat between cuts.