These delicious Butterscotch Mud Bars have an Oreo cookie crust with a fudgy homemade brownie layer, topped with a silky smooth butterscotch mousse topping. I could eat each one of these layers as a dessert on its own, but putting them together creates a triple threat (in the best way!) of a dessert! Love chocolate even more than butterscotch? Donโt miss my Chocolate Mud Bars. They are the ultimate treat for serious chocolate lovers!

Ingredients & Substitutions
- Crust: This easy crust is made with crushed Oreo cookies and melted butter. It is simple and full of rich chocolate flavor. For the best texture, use a food processor to get fine, even crumbs. If you want to switch it up, try chocolate wafers instead.
- Brownies: This is my favorite brownie base for a 9ร13-inch pan. I also use it in my French Silk Brownies because itโs just that good. (So, don’t eat them all before assembling the dessert!)
- Pudding Mix: Use a 3.9-ounce box of butterscotch instant pudding mix for the rich and creamy chocolate mousse layer.
- Milk: For the creamiest texture in the mousse, whole milk works best. You can use 2% or 1%, but the consistency may be slightly thinner.
- Whipped Cream: Store-bought whipped topping works just fine, but for the best flavor and texture, homemade whipped cream is even better. Youโll use half for the mousse layer and save the rest for the topping.

Can I Use Store-Bought Brownie Mix?
Yes, you can use a boxed brownie mix to save time! Just prepare the mix according to the package instructions and pour it over the Oreo crust as directed in the recipe. Keep in mind that homemade brownies give the bars a richer, more decadent flavor, but the boxed mix works in a pinch and still tastes delicious.
Can I Make Butterscotch Mud Bars Ahead of Time?
Yes! These dessert bars have a few layers, which makes them perfect for prepping in stages. You can bake the Oreo crust and brownie layer a day or two in advance and store them in an airtight container at room temperature. The butterscotch mousse can also be mixed ahead of time and kept in the refrigerator overnight. Since the finished bars need time to chill before serving, making them ahead is actually ideal!
Can I Use a Different Flavor of Pudding for the Mousse Layer?
Definitely! While butterscotch pudding gives these bars their signature flavor, you can easily swap it out for another instant pudding flavor like vanilla, chocolate, or even banana. Just make sure to use the same size box (3.9 ounces) of instant pudding mix. Itโs a fun way to customize the bars based on what you love or what you have on hand.

How To Store Butterscotch Mud Bars
Store the bars covered in the refrigerator for up to 4โ5 days. To keep the topping fresh and the layers intact, use plastic wrap, aluminum foil, or an airtight container. For the best texture and flavor, serve chilled straight from the fridge.
Can I Freeze Butterscotch Mud Bars?
Yes, you can freeze Butterscotch Mud Bars to enjoy later! For best results, freeze them before adding the whipped cream topping. Wrap the bars tightly in plastic wrap and then aluminum foil, or store them in an airtight container. They can be frozen for up to 2 months. When ready to serve, thaw overnight in the refrigerator and add the whipped cream topping.

Butterscotch Mud Bars
Ingredients
Crust
- 30 Oreo cookies
- ยฝ cup (1 stick / 113 g) unsalted butter, melted
Brownie Layer
- 1 ยฝ cups (187.5 g) all-purpose flour
- โ cup (42 g) unsweetened cocoa powder
- ยฝ teaspoon baking powder
- ยผ teaspoon kosher salt
- 4 large eggs, room temperature
- 2 cups (400 g) granulated sugar
- ยพ cup (1 ยฝ sticks / 170 g) unsalted butter, room temperature
- 2 teaspoons vanilla extract
Butterscotch Mousse Layer
- 2 cups (490 g) whole milk
- 1 package (3.4 ounces) instant butterscotch pudding mix
- ยฝ cup (62.5 g) confectionersโ sugar
- 16 ounces whipped topping, divided
Instructions
- Preheat oven to 350ยฐF. Spray a 9ร13-inch baking dish with nonstick spray.
- Using a food processor, pulse the Oreo cookies into fine crumbs.
- In a large bowl, combine the cookie crumbs and melted butter. Mix until fully combined. Press the mixture evenly into the bottom of the prepared baking dish. Set aside.
- In a medium bowl, whisk together the flour, cocoa powder, baking powder, and salt.
- In a separate large bowl or the bowl of a stand mixer with the paddle attachment, beat the eggs, sugar, butter, and vanilla extract on medium-high speed until light and fluffy, about 2โ3 minutes.
- Gradually add the dry ingredients to the wet ingredients, mixing on low speed just until combined. Avoid overmixing.
- Carefully spread the brownie batter over the Oreo crust. Bake for 25โ30 minutes, or until the center is just set and a toothpick inserted comes out with a few moist crumbs.
- Remove from the oven and let cool completely.
- While the brownie layer cools, prepare the mousse. In a large bowl, whisk together the milk, pudding mix, and confectionersโ sugar for about 2 minutes, until the pudding starts to thicken.
- Gently fold in half (8 ounces) of the whipped topping until smooth and fully combined, saving the remaining whipped topping for the topping.
- Spread the mousse evenly over the cooled brownie layer.
- Chill the assembled dessert in the refrigerator for at least 1 to 1 ยฝ hours before serving.
- Once chilled, spread the remaining whipped topping evenly over the mousse. Enjoy immediately, or cover and store in the refrigerator until ready to serve.
Did you make this recipe?
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What the Test Kitchen had to say about this recipe:

Autumn
These bars are SO delicious! I love the butterscotch pudding layer with the Oreo crust!

Elizabeth
I am not a huge butterscotch dessert person, but I LOVED these bars. Oh, my…I had to walk away quickly!

Bella
These bars are so delicious. They are a decadent dessert, for sure.

Stephanie
Wow. These seem fancy, but they are really easy to put together. I want to try them with other pudding flavors, too.