This One-Bowl Peanut Butter Sheet Cake is a dreamy dessert that’s as easy to make as it is delicious. In just 25 minutes of prep, you’ll create a moist, tender cake with a rich peanut butter flavor that’s perfectly balanced. The smooth, creamy frosting adds a luscious finish, making every bite irresistible. Whether you’re hosting a gathering or treating yourself, this cake is a guaranteed crowd-pleaser.
Bake it in 24 minutes, and you’ll be rewarded with a dessert that’s both comforting and indulgent. The cake’s soft crumb pairs beautifully with the velvety frosting, creating a harmony of textures and flavors. Peanut butter lovers will adore the nutty sweetness, while the simplicity of one-bowl prep ensures minimal cleanup. It’s the perfect treat for any occasion, ready to impress with minimal effort.
Ingredients for One-Bowl Peanut Butter Sheet Cake
- 2 cups (16 oz/450 g) granulated sugar
- 1 cup (8 fl oz/240 ml) hot water
- ½ cup (4 oz/115 ml) creamy peanut butter
- ¾ cup (6 oz/170 g) butter, melted
- ½ cup (4 fl oz/120 ml) buttermilk (at room temperature)
- ¼ cup (2 fl oz/60 ml) vegetable oil
- 2 large eggs (at room temperature)
- 1 teaspoon vanilla extract
- ½ teaspoon baking soda
- ¼ teaspoon salt
- 2 cups (10 oz/284 g) all-purpose flour
- 1 recipe Peanut Butter Frosting
- Shaved chocolate and chopped peanuts (optional, for garnish)
Step-by-Step Instructions
- Preheat the oven to 350°F (180°C). Butter and flour an 11 x 17-inch (28 x 43-cm) jelly roll pan. Set aside.
- In a large mixing bowl, whisk together the sugar, hot water, and peanut butter until smooth.
- Stir in the melted butter, buttermilk, vegetable oil, eggs, vanilla extract, baking soda, and salt. Whisk until the mixture is smooth and well combined.
- Fold in the flour gently until evenly incorporated. Spread the batter evenly into the prepared pan.
- Bake for 22 to 24 minutes, or until a toothpick inserted into the center comes out clean.
- Let the cake cool completely in the pan before frosting with Peanut Butter Frosting.
- Garnish with shaved chocolate and chopped peanuts if desired. Serve directly from the pan.
- Store any leftovers in an airtight container at room temperature for up to 3 days.
Perfect Pairings: Sauce and Topping Ideas
While the Peanut Butter Frosting is a star on its own, you can elevate this cake with a drizzle of chocolate ganache or a dollop of whipped cream. For a fruity twist, add a layer of strawberry jam before frosting. If you’re feeling adventurous, sprinkle with sea salt for a sweet-and-salty finish.
Serve It Up: Creative Serving Suggestions
This sheet cake is perfect for casual gatherings—serve it straight from the pan for a rustic vibe. For a fancier presentation, cut it into squares and plate with a dusting of powdered sugar or a side of vanilla ice cream. It’s also a great addition to a dessert buffet alongside brownies and cookies.
Keep It Fresh: Storage and Reheating Tips
Store leftovers in an airtight container at room temperature for up to 3 days. If you prefer a warm slice, pop it in the microwave for 10-15 seconds to soften the frosting and bring out the peanut butter flavor. For longer storage, wrap individual pieces in plastic wrap and freeze for up to 2 months.
Mix It Up: Recipe Variations to Try
Swap the peanut butter for almond butter or sunflower seed butter for a nut-free version. Add a handful of chocolate chips or chopped Reese’s cups to the batter for extra indulgence. You can also experiment with different flours, like whole wheat or gluten-free blends, for a unique twist.
Quick Tips: Time-Saving Hacks
To speed up prep, use a stand mixer to combine the ingredients quickly. If you’re short on time, skip the frosting and dust the cake with powdered sugar instead. For an even faster bake, preheat your oven while you gather and measure your ingredients.
One-Bowl Peanut Butter Sheet Cake
Ingredients
- 2 cups granulated sugar 16 oz/450 g
- 1 cup water hot, 8 fl oz/240 ml
- ½ cup creamy peanut butter 4 oz/115 ml
- ¾ cup butter melted, 6 oz/170 g
- ½ cup buttermilk at room temperature, 4 fl oz/120 ml
- ¼ cup vegetable oil 2 fl oz/60 ml
- 2 large eggs at room temperature
- 1 teaspoon vanilla extract
- ½ teaspoon baking soda
- ¼ teaspoon salt
- 2 cups all-purpose flour 10 oz/284 g
Peanut Butter Frosting
- Shaved chocolate and chopped peanuts for garnish (optional)
Instructions
- Preheat the oven to 350°F (180°C) and butter and flour an 11 x 17-inch (28 x 43-cm) jelly roll pan. Set aside
- In a large mixing bowl, whisk together the sugar, hot water, and peanut butter until smooth.
- Stir in the melted butter, buttermilk, vegetable oil, eggs, vanilla extract, baking soda, and salt and again, whisk until smooth.
- Fold in the flour until evenly combined, then spread in the prepared pan.
- Bake for 22 to 24 minutes, until a toothpick inserted in the center comes out clean. Let cool in the pan completely before frosting with Peanut Butter Frosting.
- Garnish with shaved chocolate and chopped peanuts if you wish and serve straight from the pan. Store leftovers in an airtight container at room temperature for up to 3 days.
