One-Bowl Vanilla Sheet Pan Cake
This one-bowl vanilla sheet pan cake is the answer when you need a simple, crowd-pleasing dessert that bakes in under 20 minutes.
It stays moist for days, and a thick layer of fudgy chocolate frosting makes it impossible to resist.
Why This Cake Works
The crumb is tender and even across the whole pan, with a golden top that never sinks or domes.
Mixing everything in one bowl means less cleanup, and the buttermilk gives it a subtle tang that balances the sweet frosting.
I keep coming back to this cake for birthdays and potlucks because it feeds a crowd without fuss.
Ingredients
- 2 ½ cups all-purpose flour: spoon and level for the lightest crumb.
- 1 ½ cups granulated sugar.
- 2 teaspoons baking powder.
- ½ teaspoon baking soda.
- ½ teaspoon salt.
- 1 cup buttermilk: at room temperature.
- ½ cup neutral oil: like vegetable or canola.
- 2 large eggs: at room temperature.
- 2 teaspoons vanilla extract.
- For the frosting:
- ½ cup unsalted butter: softened.
- 3 cups powdered sugar.
- ½ cup unsweetened cocoa powder.
- ¼ cup whole milk: plus more if needed.
- 1 teaspoon vanilla extract.
- Pinch of salt.
Variations / Substitutions
- Buttermilk substitute: mix 1 cup milk with 1 tablespoon lemon juice; let it sit 5 minutes until thickened.
- Dairy-free: use a neutral oil and your favorite unsweetened plant milk. Swap the butter in the frosting for a vegan butter stick.
- Gluten-free: a good 1:1 gluten-free baking flour blend works well here.
If you love citrus, try our Lemon Blueberry Sheet Pan Cake.
How to Make Vanilla Sheet Pan Cake
Step 1: Mix the Batter
Preheat your oven to 350°F (175°C) and grease a 13×18-inch half sheet pan with butter or nonstick spray. In a large bowl, whisk together the 2 ½ cups flour, 1 ½ cups sugar, 2 teaspoons baking powder, ½ teaspoon baking soda, and ½ teaspoon salt. Add the 1 cup buttermilk, ½ cup oil, 2 large eggs, and 2 teaspoons vanilla. Stir with a whisk or spatula just until no streaks of flour remain. The batter will be thick and pale yellow.
Pour the batter into the prepared pan. Use a spatula to spread it into an even layer, pressing gently into the corners so the edges bake at the same pace as the center. The surface should look smooth and slightly glossy.
Step 2: Bake the Cake
Slide the pan into the oven and bake for 18 to 22 minutes. The cake is done when the top turns a light golden brown and a toothpick inserted in the center comes out with a few moist crumbs clinging to it.
You will also notice the cake spring back lightly when you press the center, and the edges will pull just slightly away from the pan. Let it cool completely in the pan set on a wire rack, about 45 minutes. Rushing this step will melt the frosting later.
Step 3: Whisk the Frosting
While the cake cools, make the frosting. In a medium bowl, beat the ½ cup softened butter with an electric mixer until creamy, about 1 minute. Gradually add the 3 cups powdered sugar and ½ cup cocoa powder, mixing on low to contain the cloud. Pour in the ¼ cup milk, 1 teaspoon vanilla, and a pinch of salt. Increase the speed and beat until the frosting is thick, glossy, and spreadable, like thick peanut butter.
If the frosting feels too stiff, stir in a splash more milk, a teaspoon at a time. If it gets too thin, a little extra powdered sugar will firm it back up. The consistency should hold a soft peak but still drag easily under a spatula.
Step 4: Frost and Slice
Once the cake is completely cool, dollop the frosting all over the top. Use an offset spatula or a butter knife to spread it in even sweeps, right to the edges. Create soft swoops and swirls on the surface for that homemade look.
Slice the cake into generous squares while it is still in the pan. If you like, scatter a handful of sprinkles or chocolate shavings over the top before serving. The first cut reveals the tender, pale crumb beneath the dark frosting, and it disappears fast.
Tips for the Best Sheet Pan Cake
- Use room temperature eggs and buttermilk so the batter comes together smoothly and bakes evenly.
- Once the flour is in, mix just until combined. Overmixing develops gluten and makes the cake tough.
- For easy cleanup and lifting, line the pan with parchment paper before greasing. You can slide the whole cake out onto a cutting board.
- A 9×13 inch pan also works; the batter will be thicker and needs an extra 5 to 8 minutes in the oven.
- For clean, crumb-free slices, wipe the knife with a damp paper towel between cuts.
Bake times shift with pan size.
| Pan Size | Approximate Thickness | Bake Time |
|---|---|---|
| 13×18 inch half sheet | ½ inch | 18 to 22 mins |
| 9×13 inch | 1 inch | 25 to 30 mins |
Keeping the Cake Fresh
Refrigerate: Store leftover cake covered at room temperature for up to 3 days. For longer storage, refrigerate in an airtight container for up to 1 week. Let it come to room temperature before serving for the softest texture.
Frequently Asked Questions
Can I use a different frosting?
Yes, a tangy cream cheese frosting or a classic vanilla buttercream are both delicious. Just scale the frosting recipe to cover a 13×18 inch surface.
Can I make this cake ahead of time?
Absolutely. Bake the cake, cool it completely, then wrap it tightly in plastic. It stays moist at room temperature for up to 2 days unfrosted. Frost it the day you plan to serve.
Why did my cake turn out dense?
The two biggest culprits are packing too much flour into the measuring cup and overmixing the batter. Spoon the flour into the cup and level it, and stop mixing as soon as the ingredients come together.
Can I freeze the unfrosted cake?
Yes. Wrap the cooled cake securely in plastic wrap, then a layer of foil. Freeze for up to 2 months. Thaw overnight in the fridge before frosting.
Vanilla Sheet Pan Cake Recipe
Ingredients
Method
- Preheat the oven to 350°F (175°C). Grease a 13×18-inch half sheet pan.
- In a large bowl, whisk together the flour, sugar, baking powder, baking soda, and salt. Add the buttermilk, oil, eggs, and vanilla; mix just until smooth.
- Pour the batter into the pan and spread it evenly, pushing it into the corners.
- Bake for 18 to 22 minutes, until golden and a toothpick inserted in the center comes out with moist crumbs. Cool completely in the pan on a wire rack.
- For the frosting, beat the butter until creamy. Gradually add the powdered sugar and cocoa powder, then mix in the milk, vanilla, and salt. Beat until thick and spreadable, adjusting consistency with extra milk or sugar if needed.
- Spread the frosting over the cooled cake. Slice into squares and serve.
