Whatever the occasion, celebrate with this Fudge Sundae Cake — a showstopping layered chocolate dessert inspired by a classic fudge sundae. It features three rich dark chocolate cake layers, a silky vanilla buttercream, a glossy dark chocolate ganache drip, and playful toppings like sprinkles, chopped nuts, and maraschino cherries. The combination of intense chocolate cake and light meringue-style buttercream creates an indulgent yet balanced cake that looks as festive as it tastes.
This cake begins with a nearly black, fudgy chocolate batter that bakes into deep-flavored layers. A cloud-like vanilla buttercream (prepared as a stabilized Swiss meringue-style buttercream) keeps the texture light, while the ganache adds a glossy, fudgy finish. Finish with colorful sprinkles and bright cherries for a celebratory touch — perfect for birthdays, holidays, or any time you want an impressive dessert.
How to make this fudge sundae cake
Make the cake
Start by combining boiling water and dark chocolate, stirring until melted and smooth. In a mixer, whip the eggs until light and frothy, then add vegetable oil and mix until incorporated. Add the granulated sugar, milk, and the warm chocolate mixture, mixing until just combined. Fold in the dry ingredients — baking cocoa, all-purpose flour, baking soda, and baking powder — until the batter is uniform and free of lumps. Divide the batter evenly between three 6″ cake pans and bake at 350°F (175°C) for about 30–35 minutes, or until a toothpick inserted into the center comes out clean. Allow the cakes to cool, then wrap and chill until firm for easier leveling and stacking.
Prepare the ganache
While the cakes bake, make the ganache by bringing heavy cream and coarsely chopped dark chocolate together until the chocolate melts. Heat briefly and stir gently with a spatula until the mixture is smooth and glossy. Avoid whisking so you don’t introduce air bubbles. Let the ganache cool until it thickens to a spreadable, fudge-like consistency before using.
Make the vanilla buttercream
For a smooth, stable buttercream, heat water and granulated sugar in a small saucepan until the syrup becomes clear. Whip egg whites in a stand mixer to stiff peaks, then slowly stream the hot sugar syrup into the whites while the mixer runs. Continue whipping until the meringue cools to room temperature. Reduce the mixer speed and add room-temperature butter in pieces, then add vanilla extract. Increase speed and whip until the buttercream is silky and spreadable. If the buttercream becomes too soft, chill briefly and rewhip before frosting.
Assemble the cake
Level cake layers if needed. Place the first layer on a cake board or plate and spread a generous layer of frosting. Stack the second and third layers with frosting between each. Apply a thin crumb coat to the top and sides, then refrigerate until firm (about 15 minutes). Finish with a final smooth layer of buttercream. If you plan to add sprinkles to the sides, press them on while the frosting is slightly tacky.
Warm the ganache if it has become too firm, then spread a thin layer across the top and use a piping bag to create controlled drips around the edges. Add remaining ganache to the top and smooth with an offset spatula. Decorate the top with extra frosting dollops, sprinkles, chopped nuts, and maraschino cherries for a true “fudge sundae” look.
Ingredients
For the chocolate cake
- 1 cup boiling water
- 2 oz dark chocolate, coarsely chopped
- 2 eggs
- ½ cup vegetable oil
- 2 cups granulated sugar
- 1 cup milk
- 4 oz baking cocoa
- 1 ¼ cups all-purpose flour
- 1 tsp baking soda
- ½ tsp baking powder
For the vanilla buttercream
- ½ cup water
- 1 ¾ cups granulated sugar
- 8 egg whites
- 1 lb unsalted butter, at room temperature
- 1 tsp vanilla extract
For the dark chocolate ganache
- 4 oz dark chocolate (about 60% cocoa), coarsely chopped
- 4 oz heavy cream
Garnish
- Sprinkles
- Coarsely chopped nuts
- Maraschino cherries
Instructions
- Combine boiling water and dark chocolate in a small bowl. Stir until smooth and set aside to cool slightly.
- In a stand mixer, whip eggs until light and frothy. Add vegetable oil and mix until incorporated.
- Add sugar, milk, and the chocolate mixture. Mix until just combined.
- Fold in cocoa, flour, baking soda, and baking powder until the batter is even and lump-free.
- Divide batter evenly among three 6″ cake pans and bake at 350°F (175°C) for 30–35 minutes, or until a toothpick comes out clean.
- Cool pans until safe to handle, then transfer cakes to plastic wrap and refrigerate until cool and firm.
- For the ganache, heat cream and chocolate together until the chocolate melts. Stir with a spatula until smooth and let cool to a thick, spreadable consistency.
- To make the buttercream, heat water and sugar until clear. Whip egg whites to stiff peaks, then slowly pour in the hot syrup while mixing. Whip until the mixture cools to room temperature, then add butter in pieces. Add vanilla and whip until smooth.
- Level cake layers, then stack with a thick layer of frosting between each layer. Apply a thin crumb coat and chill until firm.
- Finish frosting the cake smoothly. Chill briefly if needed, then add a thin layer of ganache to the top and use a piping bag to create drips down the sides. Smooth ganache on the top.
- Garnish with sprinkles, chopped nuts, additional frosting, and maraschino cherries. Chill briefly to set before serving.
Notes and tips
- Portion the batter: For even layers, weigh or measure batter so each pan receives roughly the same amount. This recipe yields three 6″ layers.
- Avoid air bubbles in ganache: Stir ganache with a spatula rather than whisking to keep it smooth and free of bubbles.
- Chill between steps: Chilling the cakes after baking and using a chilled crumb coat makes stacking and smoothing the final frosting easier.
- Remove frosting air bubbles: If the buttercream is aerated, reduce the mixer speed to low and beat until smooth (3–5 minutes).
- Smoothing tools: A rotating cake stand and a bench scraper help achieve a professional finish. Warm a spatula or scraper and wipe it clean before a final pass for a sleek look.
- Perfect ganache drip: Let the ganache cool to a thick fudge-like consistency before piping drips. Use a piping bag to control each drip and then fill and smooth the center.
- Storage: Uncut, the cake keeps at room temperature for 3–4 days if covered. Once cut, protect exposed slices with plastic wrap and refrigerate if your kitchen is warm.
- Chocolate cake recipe adapted from Miette (adaptation credited to the original source).
Nutrition (approximate)
- Serving size: 1 slice
- Calories: 597
- Sugar: 53.4 g
- Sodium: 287 mg
- Fat: 37.5 g
- Saturated fat: 20.7 g
- Carbohydrates: 65.7 g
- Fiber: 3 g
- Protein: 6.6 g
- Cholesterol: 95 mg
Final thoughts
This Fudge Sundae Cake is a great choice when you want a dessert that’s rich in chocolate flavor but still visually playful and festive. The contrast between a deeply chocolatey cake and a light, silky buttercream keeps each slice satisfying without feeling overly heavy. If you make it, consider sharing a photo on social media and tagging your post with the hashtag #thesimplesweetlife — it’s always a treat to see your creations.
If you liked this recipe, you might also enjoy:
- Peanut butter whiskey brownies
- Anything But Basic Cake (with multiple variations)
- Hot chocolate cake
Update notes: This recipe was originally published in 2016 and updated with additional tips and an improved format in 2020.