The Famous Robert St John Chocolate Cake: A Decadent Recipe

Some recipes are more than just a list of ingredients; they’re legends. They’re the desserts you hear whispered about, the ones served at celebrated restaurants that you dream of recreating at home. The Robert St John Chocolate Cake is one of those legends. This is not your average weeknight chocolate cake. It is a masterpiece of deep, dark chocolate flavor, featuring an incredibly moist cake, a tangy chocolate cream cheese filling, and a rich, fudgy sour cream icing. While it may seem like a professional-level undertaking, this guide will walk you through every step to create this show-stopping, decadent dessert in your own kitchen.

Ingredients for This Decadent Cake

This cake is a three-part harmony of chocolate goodness. For the best results, bring your refrigerated ingredients like eggs, butter, cream cheese, buttermilk, and sour cream to room temperature before you begin.

Component	Ingredient	Amount/Quantity
For the Chocolate Cake	Cake flour	1 ¾ cups
	Dutch-processed cocoa powder	¾ cup
	Baking soda	2 teaspoons
	Baking powder	1 teaspoon
	Kosher salt	½ teaspoon
	Large eggs, room temperature	2
	Granulated sugar	2 cups
	Unsalted butter, melted	¾ cup
	Buttermilk, room temperature	1 cup
	Brewed coffee, room temperature	1 cup
	Pure vanilla extract	1 teaspoon
For the Filling	Semisweet chocolate pieces	1 ½ cups
	Cream cheese, softened	8 ounces
	Powdered sugar	¾ cup
For the Icing	Unsweetened chocolate	6 ounces
	Unsalted butter, softened	½ cup
	Powdered sugar	4 cups
	Sour cream, room temperature	1 cup
	Pure vanilla extract	1 Tablespoon

Timing

This is a project cake, perfect for a weekend baking session. The time invested is paid back in every single decadent bite.

• Preparation Time: 40 minutes
• Cooking Time: 35 minutes
• Cooling & Assembly Time: 2 hours
• Total Time: Approximately 3 hours, 15 minutes

Step-by-Step Instructions

Let’s break down this legendary cake into manageable steps. We’ll make the cake layers first, then the filling and icing while they cool.

Step 1: Preheat Oven and Prepare Cake Pans

First, preheat your oven to 350°F (175°C). Grease and flour two 9-inch round cake pans. For extra insurance against sticking, you can also line the bottoms with parchment paper.

Step 2: Whisk the Dry Ingredients

In a large bowl, whisk together the cake flour, Dutch-processed cocoa, baking soda, baking powder, and kosher salt. Whisking thoroughly combines and aerates the ingredients, ensuring a light, even crumb. Set this bowl aside.

Step 3: Combine the Wet Ingredients

In another large bowl, beat the eggs and sugar together with an electric mixer until light and fluffy, about 2 minutes. On low speed, stream in the melted butter, buttermilk, room-temperature coffee, and vanilla extract. Mix until just combined.

Step 4: Mix the Batter and Bake

Pour the wet ingredients into the bowl with the dry ingredients. Mix on low speed until just combined. Do not overmix! Scrape down the sides of the bowl to ensure there are no dry pockets. The batter will be thin. Divide the batter evenly between your two prepared cake pans. Bake for 30-35 minutes, or until a wooden skewer inserted into the center comes out clean. Let the cakes cool in the pans for 15 minutes before inverting them onto a wire rack to cool completely.

Step 5: Prepare the Cream Cheese Filling

While the cakes are cooling, make the filling. Gently melt the semisweet chocolate pieces over a double boiler or in the microwave in 30-second intervals, stirring until smooth. In a separate bowl, beat the softened cream cheese and powdered sugar with an electric mixer until smooth and creamy. Add the melted chocolate and beat until well combined and fluffy.

Step 6: Make the Chocolate Fudge Icing

Now for the final decadent layer. Melt the unsweetened chocolate over a double boiler. In a large bowl using an electric mixer, cream together the softened butter and powdered sugar. Add the melted (but not hot) chocolate and vanilla extract and beat until light and fluffy. Finally, beat in the sour cream until the icing is smooth and spreadable. Use immediately for the best consistency.

Step 7: Assemble Your Robert St John Chocolate Cake

Once the cake layers are completely cool, your masterpiece is ready to assemble. Place one cake layer on your serving platter. Spread the chocolate cream cheese filling evenly over the top. Place the second cake layer on top of the filling. Generously frost the top and sides of the entire cake with the rich chocolate fudge icing.

Nutritional Information

This is a truly indulgent dessert, perfect for special occasions. The following is an estimation per slice, assuming the cake is cut into 16 slices.

• Calories: ~650 kcal
• Protein: 7 g
• Fat: 35 g
• Carbohydrates: 80 g (Sugar: 65 g)

Indulgent Variations

This cake is designed for decadence, so “healthier” is relative. Here are a few small tweaks you can consider.

• Greek Yogurt Swap: You can substitute full-fat plain Greek yogurt for the sour cream in the icing for a slightly tangier flavor and a bit of extra protein.
• High-Quality Chocolate: Using a high-quality dark chocolate (70% cacao or higher) for the filling and icing can add complex flavor notes and potential antioxidant benefits.

Serving Suggestions

A slice of this rich cake is a dessert experience all on its own.

• Classic Pairing: Serve with a tall glass of cold milk to cut through the richness.
• A La Mode: A small scoop of high-quality vanilla bean ice cream or raspberry sorbet is a perfect companion.
• For Celebrations: This cake is the ultimate show-stopper for birthdays, anniversaries, or holiday gatherings.

Common Mistakes to Avoid

For a cake this special, a few key details make all the difference.

• Frosting a Warm Cake: This is the #1 rule of cake assembly. If your cake layers are even slightly warm, the filling and icing will melt into a soupy mess. Solution: Be patient! Ensure your cake layers have cooled completely to room temperature before you even think about frosting them.
• Using Cold Ingredients: Room temperature ingredients (eggs, buttermilk, cream cheese, sour cream) emulsify better, creating a smoother batter and creamier fillings/icings. Solution: Take your refrigerated ingredients out at least 30-60 minutes before you start baking.
• Overmixing the Batter: Overmixing after adding the flour develops gluten, which can make your cake tough and dense instead of tender and moist. Solution: Mix on low speed and stop as soon as the last streak of flour disappears.
• Seizing the Chocolate: Overheating or getting water into your chocolate while melting will cause it to seize into a grainy, unusable paste. Solution: Melt chocolate gently over a double boiler (not allowing the water to touch the bowl) or in the microwave in short, 20-30 second bursts, stirring in between.

Storing Tips

Due to the cream cheese and sour cream in the filling and icing, this cake must be refrigerated.

• Refrigerate: Store the cake in an airtight cake carrier or cover it loosely in the refrigerator for up to 5 days.
• Serving: For the best flavor and texture, let the cake sit at room temperature for about 20-30 minutes before serving.
• Freezing: You can freeze individual slices or the whole cake. Wrap slices tightly in plastic wrap and then foil. The cake will keep in the freezer for up to 3 months. Thaw in the refrigerator overnight.

Conclusion

The Robert St John Chocolate Cake is more than just a dessert; it’s a baking project that promises an incredibly rewarding and delicious result. Every layer—from the coffee-infused moist chocolate cake to the tangy cream cheese filling and the rich fudge icing—is designed for pure chocolate bliss. It’s the perfect recipe to tackle when you want to create something truly special and unforgettable. We hope you enjoy the process of making and, of course, eating this legendary cake. Let us know how it turns out in the comments below!

FAQs

Q1. Why does the cake recipe use coffee? Will it taste like coffee?

The coffee’s purpose is to enhance and deepen the chocolate flavor. It makes the chocolate taste richer and more complex. The final cake will not taste like coffee at all—it will just taste like the best, most chocolatey cake you’ve ever had.

Q2. What is Dutch-processed cocoa and can I use regular cocoa powder?

Dutch-processed cocoa has been treated to neutralize its acidity, resulting in a darker color and a smoother, less bitter flavor. While you can use regular unsweetened cocoa powder, the cake’s flavor will be slightly more acidic and its color will be lighter. For the deep, rich flavor this cake is known for, Dutch-processed is recommended.

Q3. Can I make this cake in advance?

Yes! This is a great cake to make ahead of time. You can bake the cake layers a day in advance, let them cool completely, and wrap them tightly in plastic wrap at room temperature. You can then make the filling and icing and assemble the cake the next day.

Q4. Can I make this in three 8-inch pans instead of two 9-inch pans?

Absolutely. If you use three 8-inch pans, the layers will be slightly thinner. You will need to reduce the baking time, so start checking for doneness around the 25-minute mark.