Peanut Butter Brownies with Peanut Frosting
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These peanut butter brownies are the ultimate treat! It’s our favorite fudgy brownie recipe studded with crunchy peanut bits and topped with a layer of peanut butter frosting, a layer of chocolate, and a sprinkle of sea salt. They’re always a hit, they’re easy to make, and they’re ready in just 45 minutes!
I set out to make peanut butter brownies and ended up with our all-time favorite version. These are rich, fudgy brownies studded with crunchy peanuts, topped with smooth peanut butter frosting, finished with glossy chocolate ganache, and sprinkled with Maldon sea salt.
I love how each layer brings something different. The brownie base is dense and chocolatey with a bit of crunch, the frosting adds a creamy, nutty sweetness, and the ganache ties it all together with a silky finish. That final hit of flaky salt makes every bite pop.
They look a little impressive, but each layer is simple to make, and the payoff is huge. This is the kind of dessert I bring out for special occasions—and always make sure to grab one early because they disappear fast.
Tips for making the best peanut butter brownies
Even though this recipe is simple, a few small details make a big difference in the final texture and flavor:
- Don’t overmix the batter. I gently fold everything together with a spatula just until combined. This keeps the brownies soft and fudgy, rather than dense or tough.
- Use a metal baking pan. It heats more evenly and helps create that perfect balance of set edges and a rich, gooey center. Glass or ceramic can work, but they may need extra bake time and can cook less evenly.
- Start with room-temperature eggs. They blend more smoothly into the batter, giving you a better texture. I either take them out ahead of time or let them sit in warm water while I prep the rest.
Storage
- Storing: Store brownies in an airtight container at room temperature for 2-3 days. You can prolong this by a day or two by storing them in the fridge.
- Freezing: Once frosted, store them in an airtight container or wrap them well, and they’ll keep in the freezer for up to 3 months.
Peanut Butter Brownies with Peanut Frosting
Ingredients
Brownies
- ½ cup butter (room temperature)
- ¼ cup neutral-flavored oil (such as canola or avocado)
- 5 ounces dark chocolate chips (about ¾ cup)
- 1 cups granulated sugar
- 2 teaspoons vanilla extract
- 3 large eggs
- 1 cup all-purpose flour
- ¼ cup cocoa powder
- ¼ teaspoon baking powder
- ½ teaspoon salt
- 1 cup roasted salted peanuts (optional)
Frosting
- ½ cup natural peanut butter
- 2 tablespoons salted butter (room temperature)
- ½ cup powdered sugar
- 1 teaspoon vanilla extract
- 1-2 tablespoon whole milk
Ganache
- 5 ounces dark chocolate
- ½ cup heavy cream
Instructions
- Preheat your oven to 350 degrees Fahrenheit. Line a 9×9 inch square baking pan with parchment paper and grease it with butter. Place the butter and chocolate in a mixing bowl and microwave for 1 minute. Stir the chocolate until it's melted and smooth. Add the sugar, oil, and vanilla to the chocolate and whisk to combine. Add the eggs and whisk again.½ cup butter, ¼ cup neutral-flavored oil, 5 ounces dark chocolate chips, 1 cups granulated sugar, 2 teaspoons vanilla extract, 3 large eggs
- In a medium-sized bowl, whisk the flour, cocoa powder, salt, and baking powder. Mix the dry ingredients with the wet ingredients. If using, fold the peanuts into the batter.
- Pour the batter into the baking dish and smooth the top. Bake for 25-30 minutes, or until a toothpick inserted into the center comes out clean.1 cup all-purpose flour, ¼ cup cocoa powder, ¼ teaspoon baking powder, ½ teaspoon salt, 1 cup roasted salted peanuts
- When the brownies are mostly cool, make the frosting. Use electric beaters to beat the peanut butter, butter, powdered sugar, and vanilla. Add 1 tablespoon of the milk and beat again. If you'd like a thinner frosting, add the second tablespoon. Spread the frosting over the brownies in the pan.½ cup natural peanut butter, 2 tablespoons salted butter, ½ cup powdered sugar, 1 teaspoon vanilla extract, 1-2 tablespoon whole milk
- To make the chocolate topping, add the chocolate and cream to a medium-sized bowl and microwave for 1 minute. Stir until the chocolate is melted and smooth then pour it over the brownies. (Make sure that it's not hot when you pour it over!) Set the brownies aside for at least 30 minutes for the chocolate to set. Sprinkle a little sea salt over top then cut the brownies into 16 pieces.5 ounces dark chocolate, ½ cup heavy cream
Video
Nutrition
We have thoroughly tested this recipe for accuracy. However, individual results may vary. See our full recipe disclosure here.
Favorite peanut butter dessert recipes
For more sweet treats, see all of my dessert recipes!
I can’t stand how good these look!!
These look deadly–but in a good way! Yum!