If you’ve been searching for the perfect chocolate cake one that’s rich, moist, deeply chocolatey, and actually easy to make, your search ends here. This one-bowl chocolate cake is the real deal. It’s the kind of cake that disappears fast, leaving everyone asking for “just one more slice.” Whether it’s for a birthday, special celebration, or just a Tuesday pick-me-up, this recipe never fails.
Let’s get baking! You’ll be amazed at how simple (and delicious) it is!
Step-by-Step Instructions
Step 1: Prep your pans
Preheat your oven to 350°F (175°C). Grease two 8-inch round cake pans and dust them lightly with cocoa powder (this keeps the cake from sticking and adds a little extra chocolate flavor). Line the bottoms with parchment paper, trust me, it’s worth the extra step.
Step 2: Combine the dry ingredients
In a large mixing bowl, whisk together the flour, sugar, cocoa powder, baking soda, baking powder, and salt. Sifting the cocoa powder first helps keep the batter smooth and lump-free.
Step 3: Add the wet ingredients
In another bowl or large measuring cup, whisk together the oil, buttermilk, hot water, eggs, and vanilla extract. Make sure to pour the hot water in slowly so it doesn’t scramble the eggs.
Pour the wet mixture into the dry ingredients and beat on medium speed for about 2–3 minutes. The batter will look thin. Thin batter makes for a wonderfully moist cake.
Step 4: Bake the cakes
Divide the batter evenly between your two prepared pans (a kitchen scale helps if you want them perfectly even). Bake for 45 minutes, or until a toothpick inserted in the center comes out mostly clean, a few moist crumbs are perfect.
Cool the cakes in the pans for 10 minutes, then transfer to a wire rack to cool completely.
Step 5: Make the chocolate Swiss meringue buttercream
In the bowl of a stand mixer, whisk together the egg whites and sugar. Place the bowl over a pot of simmering water (make sure it doesn’t touch the water). Whisk constantly until the sugar dissolves and the mixture feels smooth and warm to the touch, or reaches 160°F on a thermometer.
Transfer the bowl back to your mixer and beat on medium-high until stiff, glossy peaks form and the bowl feels cool (about 5–10 minutes).
Switch to the paddle attachment and slowly add in the softened butter, a few cubes at a time. Don’t panic if it looks curdled, keep mixing! Once smooth, pour in the melted, cooled dark chocolate and beat until creamy and luscious.
Step 6: Assemble your cake
Place one cooled cake layer on your serving plate. Spread about 1 cup of buttercream evenly on top. Add the second layer and do a light crumb coat (a thin layer of frosting that traps loose crumbs). Chill for 20 minutes to set.
Next, spread a generous layer of buttercream over the top and sides. Smooth it out, or create swoops and swirls with an offset spatula, rustic looks just as good as perfect!
Decorate with chocolate curls, sprinkles, or flakes, and let the cake rest at room temperature before slicing.
Notes & Tips
- For a richer flavor: Replace the hot water with strong brewed coffee. It deepens the chocolate taste without adding a coffee flavor.
- Keep ingredients room temp: This helps everything blend smoothly.
- No stand mixer? You can use a hand mixer, but the Swiss meringue frosting will take a bit longer to whip up.
- Make it ahead: The cake layers can be baked and wrapped tightly in plastic for up to 2 days or frozen for up to a month.
- Decorating tip: Warm your offset spatula in hot water, wipe it dry, and glide it over the frosting for a silky-smooth finish.
Frequently Asked Questions
1. Why is my chocolate cake dense or dry?
Usually, that happens if the batter is overmixed or the cake is baked too long. Remember, this batter should be thin — that’s what keeps it moist!
2. Can I use regular cocoa powder instead of Dutch-processed?
Yes, you can. The flavor will be slightly lighter and less rich, but still delicious.
3. How can I make this cake dairy-free?
Use a plant-based milk mixed with a tablespoon of lemon juice or vinegar instead of buttermilk, and swap in vegan butter for the frosting.
4. Can I make this as cupcakes instead?
Definitely! Bake at the same temperature for about 18–22 minutes. It should make around 24 cupcakes.
5. What’s the best way to store leftover cake?
Store it covered at room temperature for up to 2 days, or in the fridge for up to 5 days. If refrigerated, let it sit out for 30 minutes before serving so the frosting softens up again.
Preheat oven to 350°F (175°C). Grease two 8-inch round baking pans and dust with cocoa powder. Line bottoms with parchment paper. Calories: Approximately 450 kcal per serving (estimated)
Protein: 5g (estimated)
Carbs: 60g (estimated)
Fat: 20g (estimated)
Ingredients
Instructions
In a large bowl, whisk together flour, sugar, cocoa powder, baking soda, baking powder, and salt.
In a separate bowl, whisk together oil, buttermilk, hot water, eggs, and vanilla. (Pour hot water slowly to avoid cooking the eggs).
Add wet ingredients to dry ingredients and mix on medium speed for 2-3 minutes. Batter will be very thin.
Pour batter evenly into prepared pans. Use a kitchen scale to ensure even distribution.
Bake for 45 minutes, or until a cake tester inserted into the center comes out mostly clean.
Cool in pans for 10 minutes, then turn out onto a wire rack to cool completely.
For the Chocolate Swiss Meringue Buttercream: Place egg whites and sugar into the bowl of a stand mixer, whisk until combined.
Place bowl over a double boiler on the stove and whisk constantly until the mixture is hot and no longer grainy to the touch (approx. 3mins). Or registers 160F on a candy thermometer.
Place bowl on your stand mixer and whisk on med-high until the meringue is stiff and cooled (the bowl is no longer warm to the touch (approx. 5-10mins)).
Switch to paddle attachment. Slowly add cubed butter and mix until smooth.
Add cooled melted chocolate and whip until smooth.
To Assemble: Place a layer of cake on a cake board or plate. Top with approximately 1 cup of buttercream and spread evenly. Place second layer on top and do a thin crumb coat on the cake. Chill for 20 minutes.
Place 1 cup of frosting on top and spread evenly. Smooth the sides and flatten the top, then use a large offset spatula to do a swirl pattern on top.
Using a piping bag fitted with a 1M tip, pipe rows of frosting around the cake, starting at the bottom. Apply even pressure as you rotate your turntable. Continue working your way up the cake to the top, making sure the seams all align at the back.
Decorate the top with chocolate curls, pearls, and flakes, if desired.Nutrition