Recipe for Hershey Bar Cake: Decadent Chocolate Layers in One Bowl

This one-bowl cake delivers layers of rich chocolate flavor with minimal effort, making it a go-to for chocolate lovers.

Using a single Hershey bar creates a dense, fudgy texture that’s impossible to resist. The recipe comes together quickly with pantry staples, requiring no special equipment or advanced techniques.

What emerges from the oven is a moist, decadent cake with deep cocoa notes and a tender crumb. The simplicity of the method ensures consistent results every time, even for beginners.

Serve warm with a scoop of vanilla ice cream or dust with powdered sugar for an elegant finish. This dessert satisfies serious chocolate cravings with every bite.

Ingredients for Recipe for Hershey Bar Cake

One bowl, one Hershey bar, and pantry staples create this decadent cake.

The chocolate bar is non-negotiable here. Hershey’s Milk Chocolate (the classic silver wrapper) melts perfectly and gives that signature fudgy texture. Most supermarkets carry it near the checkout—grab the 8 oz size. The butter should be unsalted so you control the salt content. For the cocoa powder, Hershey’s Special Dark deepens the flavor if you want an extra-rich cake.

No buttermilk? Stir 1 tbsp vinegar or lemon juice into regular milk and let it sit for 5 minutes. Out of vanilla extract? Vanilla bean paste (use the same amount) adds speckles and intensity. The flour can be swapped for gluten-free 1:1 blend with no other changes. Skip the powdered sugar dusting if you prefer a simpler finish.

This cake stays moist for 3-4 days at room temperature in an airtight container. For longer storage, refrigerate for up to 1 week or freeze slices for 3 months. Always bring to room temperature before serving for the best texture.

Step-by-Step Instructions for Hershey Bar Cake

This one-bowl method ensures a moist, rich chocolate cake with minimal cleanup.

Step 1: Melt and Combine Chocolate and Butter

Place the 1 whole Hershey Milk Chocolate Bar in a large microwave-safe bowl and chop it into small pieces. Add the 1 cup Unsalted Butter and microwave in 30-second intervals, stirring between each, until fully melted and smooth.

The mixture should be glossy and free of lumps. I always let it cool slightly for 2-3 minutes before proceeding—this prevents the eggs from cooking when added later. The chocolate-butter base forms the rich foundation of this cake.

Step 2: Whisk in Sugars and Eggs

To the chocolate-butter mixture, add the 1.5 cups Granulated Sugar. Whisk vigorously for 1 minute until fully combined. The sugar should dissolve completely into the warm chocolate, creating a thick, smooth batter.

Next, add the 2 whole Large Eggs, one at a time, whisking for 20 seconds after each. Then stir in the 2 tsp Vanilla Extract. The batter should look glossy and slightly thickened—this indicates the eggs are properly emulsified.

Step 3: Incorporate Dry Ingredients and Liquids

In the same bowl, sprinkle the 1.5 cups All-Purpose Flour, 1 tsp Baking Soda, and 0.5 tsp Salt evenly over the batter. Gently fold these in with a spatula until just combined—overmixing will make the cake dense.

Pour in the 0.5 cup Buttermilk and 0.5 cup Hot Water. The batter will thin slightly as you fold these in. Finally, add the 0.5 cup Cocoa Powder and stir until no dry streaks remain. The batter should be smooth and pourable but not runny.

Step 4: Bake Until Set

Pour the batter into a greased 9×13-inch baking pan and spread it evenly. Bake in a preheated 350°F oven for 30-35 minutes, or until a toothpick inserted into the center comes out with a few moist crumbs.

Watch for the edges to pull slightly away from the pan and the top to spring back lightly when touched. Avoid overbaking—this cake stays moist when removed just as it sets. Let it cool in the pan for 15 minutes before dusting with 0.25 cup Powdered Sugar or serving.

Common Mistakes When Making Perfect Results

Overmixing the Batter

Once you add the dry ingredients, resist the urge to beat the batter vigorously. Fold just until the flour disappears to avoid developing gluten, which creates a dense, tough cake. I use a silicone spatula and count 10-12 folds max. 💡

Skipping the Cooling Step

After melting chocolate and butter, let the mixture cool for 2-3 minutes. Adding eggs to hot chocolate will scramble them, creating unappetizing bits in your batter. I test by touching the bowl—it should feel warm but not hot.

Incorrect Pan Size

This recipe requires a 9×13-inch pan for proper baking. A smaller pan causes overflow while a larger one yields a thin, dry cake. Grease the pan well and line with parchment for easy removal.

Overbaking the Cake

Pull the cake when a toothpick comes out with a few moist crumbs, not completely clean. Overbaking at 350°F turns fudgy cake into dry, crumbly disappointment. The center should jiggle slightly when gently shaken.

Using Cold Ingredients

Room-temperature eggs and buttermilk blend smoothly into the batter. Cold ingredients can cause the melted chocolate to seize up or create a lumpy texture. I set my eggs in warm water for 5 minutes if I forget to take them out earlier.

Ignoring the Chocolate Quality

This dish relies on Hershey’s Milk Chocolate Bar for its signature flavor. Substituting with chocolate chips or other brands alters the texture and taste. The classic 8 oz bar melts perfectly and gives that nostalgic chocolate flavor. 🍫

Frequently Asked Questions