There’s something utterly irresistible about desserts that combine layers of texture and flavor—rich fudgy brownie, creamy mousse, and a satisfyingly crunchy base. That’s exactly what you get with these Butterscotch Mud Bars. The first time I made them, I was hosting a last-minute neighborhood potluck and had just enough time to whip up something impressive without breaking a sweat. Between pulsing Oreos into crumbs and folding fluffy butterscotch pudding into whipped topping, I realized these bars are the perfect mash-up of indulgent and effortless.

Whether you’re chasing nostalgia for the sweet, buttery warmth of butterscotch or simply seeking a dessert that wows with minimal fuss, this recipe delivers. The Oreo crust is sturdy enough to hold up under a gooey brownie layer, yet tender when you bite through. And the no-bake butterscotch mousse? It’s light, pudding-infused heaven that sits atop the still-warm brownie, melding into every crack. Trust me, once you’ve served these at your next gathering, people will be asking for your “secret.”

Before we dive into the steps, gather your ingredients and clear some space in the fridge—these layers need a bit of chill time. Let’s get started!

Ingredients

30 Oreo cookies
½ cup (1 stick / 113 g) unsalted butter, melted
1½ cups (187.5 g) all-purpose flour
⅓ cup (42 g) unsweetened cocoa powder
½ teaspoon baking powder
¼ teaspoon kosher salt
4 large eggs, room temperature
2 cups (400 g) granulated sugar
¾ cup (1½ sticks / 170 g) unsalted butter, room temperature
2 teaspoons vanilla extract
2 cups (490 g) whole milk
1 package (3.4 oz) instant butterscotch pudding mix
½ cup (62.5 g) confectioners’ sugar
16 oz whipped topping, divided

Steps

Prepare the Pan and Oven
Preheat your oven to 350 °F (175 °C). Lightly coat a 9×13-inch baking dish with nonstick spray, then set it on a cooling rack or sturdy surface—you’ll want it within arm’s reach.
Make the Oreo Crust
- Place the Oreo cookies (filling and all) into a food processor and pulse until you have fine, uniform crumbs. If you don’t have a processor, seal the cookies in a sturdy plastic bag and crush them with a rolling pin.
- In a large mixing bowl, stir the crumbs together with the melted butter until every bit is moistened. The mixture should hold together when you press a small handful between your fingers.
- Press the crumb mixture firmly and evenly into the bottom of your prepared pan, creating a compact, level layer. A flat-bottomed measuring cup or glass helps pack it firmly.
Combine Dry Ingredients for Brownies
In a medium bowl, whisk together the flour, cocoa powder, baking powder, and kosher salt until well blended. This step ensures that your brownie layer bakes up evenly without any lumps of cocoa or flour.
Beat the Brownie Batter
- In the bowl of a stand mixer (or a large bowl with a hand mixer), beat the room-temperature eggs, granulated sugar, room-temperature butter, and vanilla extract on medium-high speed for about 2–3 minutes. You’re aiming for a lighter, fluffy texture that’ll give the brownies lift.
- Reduce the mixer speed to low and gradually add the dry ingredients. Mix just until combined—over-mixing can lead to dense brownies, and we want that fudgy texture.
Bake the Brownie Layer
Pour the brownie batter over the Oreo crust and use a spatula to spread it into an even layer. Slide the pan into the preheated oven and bake for 25–30 minutes, or until the center is set and a toothpick inserted comes out with just a few moist crumbs attached.
Cool Completely
Remove the pan from the oven and let it cool fully on a wire rack. Cooling is essential; if the brownie is still warm when we add our mousse, it will melt and sink right in.

Continuation of Recipe & Tips

Now that your brownie layer has cooled completely and the Oreo crust is firm beneath, it’s time to bring in the star of the show: a pillowy butterscotch mousse that’s equal parts nostalgia and pure indulgence. This no-bake layer comes together in minutes and transforms these bars from “nice” to “oh wow.” Let’s dive in!

Steps

Whisk the Butterscotch Base
In a large mixing bowl, pour in 2 cups (490 g) of whole milk. Add the entire 3.4-ounce package of instant butterscotch pudding mix and ½ cup (62.5 g) confectioners’ sugar. Using a trusty whisk, stir vigorously for about 2 minutes, or until the mixture has thickened noticeably. You’ll see the color lighten and the texture become velvety—reminiscent of silky pudding.
Fold in Whipped Topping
Measure out half of your whipped topping (8 ounces) and gently fold it into the butterscotch pudding. Use a rubber spatula and work from the center outward, carrying the mixture over the edges until it’s completely incorporated. The goal is to preserve that airy, cloud-like texture, so take your time and resist the urge to overmix.
Layer the Mousse
With the brownie layer fully cooled, scoop the butterscotch mousse over the top. Spread it evenly with an offset spatula or the back of a spoon, ensuring you fill every corner and create a smooth finish. A gentle tap of the pan on the countertop helps the mousse settle and release any trapped air bubbles.
Chill to Set
Cover the pan loosely with plastic wrap and transfer it to the refrigerator. Let the bars chill for at least 1 to 1½ hours. This resting period allows the mousse to firm up and the layers to marry, giving you clean, beautiful slices later on.
Add the Final Topping
Once the mousse is set, remove the pan from the fridge. Spread the remaining 8 ounces of whipped topping in an even layer across the surface. A piping bag fitted with a star tip can give you pretty swirls, but a simple knife-spread works just as well.
Garnish and Serve
For an extra flourish, drizzle melted dark chocolate over the top or dust lightly with cocoa powder. If you’re feeling playful, sprinkle a handful of toffee bits or chopped pecans to add crunch and depth. Return briefly to the fridge—just long enough to let any drizzle set (about 10–15 minutes)—then slice into bars.

Helpful Tips & Variations

Room-Temperature Ingredients Matter: Ensuring your eggs, butter, and milk are at room temperature helps the pudding thicken properly and the brownie batter emulsify smoothly.
Packing the Crust: Use a flat-bottomed glass or measuring cup to press the Oreo crumbs firmly and evenly. A well-packed crust prevents crumbs from scattering when you slice.
Prevent a Soggy Bottom: Cooling the brownie completely before adding the mousse is crucial. If you’re short on time, pop the pan in the freezer for 15–20 minutes—just enough to firm up, not freeze solid.
Add-Ins for Texture: Fold in a handful of toffee bits, chopped pecans, or even mini chocolate chips into the mousse before chilling. The mix-ins add a delightful surprise and contrast.
Flavor Swaps: Swap half of the whipped topping for homemade stabilized whipped cream if you prefer a less sweet finish. Or, for a caramel twist, swirl in a tablespoon of salted caramel sauce before spreading the mousse.
Make-Ahead Friendly: These bars keep beautifully in the fridge for up to four days in an airtight container. Bring them to room temperature for 10 minutes before serving to soften the layers.

FAQ Section

Q1: Can I make these bars ahead of time?
Absolutely! In fact, these bars are perfect for preparing the day before you need them. Once you’ve added the final whipped topping layer, cover the pan tightly with plastic wrap and refrigerate overnight. The flavors have extra time to meld, and the mousse firms up beautifully. Just slice and serve straight from the fridge or let sit at room temperature for 10 minutes before serving for a softer bite.

Q2: What’s the best way to get clean, even slices?
For salon-worthy bars, use a sharp knife dipped in warm water and wiped dry between each cut. The heat from the knife melts through the whipped topping smoothly, and wiping off crumbs ensures you don’t drag bits from one slice to the next. A metal spatula is handy for lifting squares out of the pan without wrecking the layers.

Q3: Can I freeze these bars for longer storage?
You can freeze them for up to one month. First, flash-freeze the pan uncovered for about 1 hour so the layers set firm. Then wrap the entire pan tightly in plastic wrap and aluminum foil. To serve, thaw overnight in the fridge and bring to room temperature for about 15–20 minutes. Note that the whipped topping may weep slightly after freezing, so consider piping fresh whipped cream on top if presentation matters.

Q4: Are there any substitutions for the instant butterscotch pudding mix?
If you can’t find butterscotch pudding mix, you can substitute vanilla instant pudding plus 2 tablespoons of caramel sauce and a pinch of salt to mimic that butterscotch flavor. Whisk until thickened, then proceed as directed. The flavor won’t be identical, but it’ll still deliver a luscious, sweet mousse layer.

Q5: How can I adapt this recipe for smaller gatherings?
Simply halve all ingredients and bake in an 8×8-inch pan. Keep an eye on the baking time— brownies in a smaller pan may cook in 20–25 minutes. Chill times remain the same. You’ll end up with about 9–12 bars instead of 24, perfect for a family dessert.

Q6: What mix-ins work well in the mousse layer?
Toasty pecans, crushed toffee bits, mini chocolate chips, or even chopped Heath bars all play nicely in the butterscotch mousse. Fold in about ½ cup of your chosen mix-in right before spreading the mousse—you’ll add texture and a pleasant surprise in every bite.

Q7: Can I swap the Oreo crust for something else?
Sure—if Oreos aren’t your thing, try graham crackers, Biscoff cookies, or even crushed pretzels for a salty-sweet twist. Use the same quantity (about 30 cookies or 8 ounces of crumbs) and press with melted butter as directed. Each substitution gives the bars a unique character.

Conclusion

There you have it: rich, fudgy brownie nestled on a snappy Oreo crust, crowned with a dreamy butterscotch mousse and pillowy whipped topping. These Butterscotch Mud Bars are the kind of dessert that looks fancy but really couldn’t be simpler—no special equipment or complicated techniques required. Whether you’re feeding a crowd or treating yourself to an indulgent afternoon pick-me-up, these bars deliver big on flavor and “wow” factor.

Give them a try at your next potluck, birthday, or weekend bake-off, and don’t forget to let me know how they turn out! Share your favorite mix-ins, crust swaps, or presentation ideas in the comments below—I love seeing your creative twists. Happy baking, and here’s to sweet moments and even sweeter memories!

Butterscotch Mud Bars

Ingredients

Steps

Steps

Helpful Tips & Variations

FAQ Section

Conclusion