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Moist, Easy & Made in a 9x13 Pan!

Every year, I bake a German Chocolate Cake for my husband’s birthday. It’s his absolute favorite, so over the years, I’ve turned it into a little tradition, tweaking, testing, and perfecting a new version each time.

Last year, I tried an old-fashioned recipe baked in a 9x13 pan, and I fell in love with the simplicity. No stacking, no stress. Just a rich, moist sheet cake that’s easy to serve, store, and decorate.

This year, I set out to create my own version, one that feels homemade but stays simple enough for real life. Something that works whether you're using a boxed cake mix or making it completely from scratch.

A Fun Fact Before We Bake

German Chocolate Cake isn’t actually German. Shocking, right? It’s named after Samuel German, an American baker who created a sweet baking chocolate for Baker’s Chocolate Company in the 1850s. So really, this cake is a homegrown U.S. classic.

Yield: 12-16

Author: Kassandra

German Chocolate Sheet Cake

This German Chocolate Sheet Cake is rich, moist, and baked in a simple 9x13 pan for easy serving and storage. Made with a homemade chocolate cake mix and topped with a gooey coconut-pecan frosting, this cake is perfect for birthdays, holidays, or any chocolate craving.

Prep time: 20 MinCook time: 1 HourTotal time: 1 H & 20 M

Ingredients

For the Homemade Chocolate Cake Mix:

1 ¾ cups (220g) all-purpose flour
2 tablespoons cornstarch
1 ½ cups (300g) organic cane sugar
½ cup (40g) Dutch-process cocoa powder
1 tsp baking soda
½ tsp baking powder
½ tsp fine sea salt

To Make the Cake (add to the mix):

2 large eggs
½ cup (120ml) neutral oil or melted butter
1 cup (240ml) brewed coffee or water
1 tsp vanilla extract
½ cup (120g) sour cream or plain Greek yogurt

Optional Chocolate Frosting Layer:

½ to 1 cup chocolate frosting, store-bought or homemade

For the Coconut-Pecan Frosting:

1 cup (240ml) heavy cream
1 cup (200g) organic cane sugar
3 large egg yolks, lightly beaten
½ cup (113g) unsalted butter
1 tsp vanilla extract
1 ½ cups (130g) shredded coconut
1 cup (110g) chopped pecans

Instructions

Make the Cake Mix:

In a medium bowl, whisk together the flour, cornstarch, sugar, cocoa powder, baking soda, baking powder, and salt. Store in a sealed jar or use immediately.

Bake the Cake:

Preheat oven to 350°F (175°C). Grease a 9x13 baking pan (or see alternate bake times below).
In a large bowl, combine the cake mix with eggs, oil, brewed coffee or water, vanilla, and sour cream.
Whisk until smooth, about 1–2 minutes.
Pour into prepared pan and bake:
9x13 pan: 35 to 40 minutes
Two 8-inch rounds: 30 to 35 minutes
Cupcakes: 18 to 22 minutes
Bundt pan: 45 to 55 minutes (start checking at 40 minutes)

Make the Coconut-Pecan Frosting:

In a saucepan, whisk together the cream, sugar, egg yolks, and butter.
Cook over medium heat, stirring constantly, until thickened and glossy, about 10–12 minutes.
Remove from heat and stir in vanilla, coconut, and pecans.
Let the frosting cool to a spreadable consistency before using.

Assemble the Cake:

Once the cake is cooled, spread a thin layer of chocolate frosting on top (optional but highly recommended).
Spoon the cooled coconut-pecan frosting over the chocolate layer and spread evenly to the edges.
Optional: Pipe chocolate frosting around the edges or top with extra pecans for decoration.

Notes

Storage Tips

Store covered at room temperature for up to 2 days or refrigerate for up to 5 days.
Let the chilled cake sit at room temperature for 20 to 30 minutes before serving.
Freeze leftover slices tightly wrapped for up to 2 months.

Please note that the nutritional values provided are estimates based on standard ingredients and calculations. Actual nutrients may vary depending on specific brands and measurement variations used in preparation.

Homemade Chocolate Cake Mix (In a Jar or Bag)

Making your own cake mix is easier than you think and it gives you full control over the ingredients. I love prepping a few jars in advance so I’m always ready to bake.

Ingredients:

1 ¾ cups (220g) all-purpose flour
2 tablespoons cornstarch
1 ½ cups (300g) organic cane sugar
½ cup (40g) Dutch-process cocoa powder
1 tsp baking soda
½ tsp baking powder
½ tsp fine sea salt

Whisk everything together and store in an airtight jar or bag until you're ready to bake.

To Bake the Cake

Add these wet ingredients to your cake mix:

2 large eggs
½ cup (120ml) neutral oil or melted butter
1 cup (240ml) brewed coffee or water
1 tsp vanilla extract
½ cup (120g) sour cream or plain Greek yogurt

Whisk everything together in a large bowl until smooth. Then pour into your greased pan and bake based on the pan you're using.

Baking Times

9x13 pan: 35 to 40 minutes
Two 8-inch rounds: 30 to 35 minutes
Cupcakes: 18 to 22 minutes
Bundt pan: 45 to 55 minutes (check around 40 minutes)

Tip: Use brewed coffee instead of water to deepen the chocolate flavor.

Coconut-Pecan Frosting

Ingredients

1 cup (240ml) heavy cream
1 cup (200g) organic cane sugar
3 large egg yolks, lightly beaten
½ cup (113g) unsalted butter
1 tsp vanilla extract
1 ½ cups (130g) shredded coconut
1 cup (110g) chopped pecans

Instructions
In a medium saucepan, combine the cream, sugar, egg yolks, and butter. Cook over medium heat, stirring constantly, until thickened, about 10 to 12 minutes. Stir in vanilla, coconut, and pecans. Let cool to a spreadable texture before frosting.

How to Assemble the Cake (With/Without Chocolate Frosting)

Once your cake has cooled, it’s time to bring it all together. Traditionally, German Chocolate Cake skips the chocolate frosting layer and just uses the coconut-pecan topping. But over the years, I’ve found that adding a thin layer of chocolate frosting underneath the topping gives the cake an extra rich, decadent flavor that my family loves.

It also makes the topping easier to spread and creates a beautiful, layered look without adding any complexity.

If you’re going the quick route, I used this store-bought frosting, and it worked perfectly. But if you want to go fully homemade, try this gorgeous homemade chocolate buttercream frosting. It’s creamy, chocolatey, and totally worth the few extra minutes.

Here’s how I assemble it:

Spread a thin layer of chocolate frosting over the cooled cake
Gently spoon on the coconut-pecan topping and spread it evenly
Optional: pipe a border of frosting around the edges or garnish with extra pecans if you’re feeling fancy

And if you want to skip the chocolate frosting altogether? Go for it. This cake is amazing either way and totally stands on its own.

Storage Tips and Serving Notes

This cake stores like a dream. You can keep it covered at room temperature for up to 2 days or refrigerate it for up to 5 days. Just make sure it’s in an airtight container so the frosting stays nice and soft.

Pro tip: If it’s been chilled, let the cake sit out for 20 to 30 minutes before serving so the flavors come through beautifully. You can even warm up a slice for 10 seconds in the microwave for that just-baked coziness.

Got leftovers? It freezes well too. Slice it into portions, wrap them tightly, and freeze for up to 2 months. Perfect for future cake cravings.

♡ PIN IT FOR LATER ♡

Can I Use a Boxed Cake Mix Instead? Absolutely.

I totally get it—sometimes you just need cake now. While I love making my homemade chocolate cake mix for the control and quality, this recipe works beautifully with a boxed mix too. I’ve tested it both ways and it still delivers that rich, classic German Chocolate Cake flavor.

If you're going the shortcut route, I recommend this chocolate cake mix. It’s high quality, tastes great, and gives a perfect base for the coconut-pecan topping.

Whether it’s for a birthday, holiday gathering, or an easy weekend dessert, this cake is quick and easy to whip up. You can go fully homemade or mix-and-match based on what you’ve got and how much time you want to spend. Either way, it’s going to taste like something special.

Other Ways to Use This Cake Mix

Your homemade mix doesn’t stop at cake. You can also make:

Cake mix cookies
Cake mix brownies
Cake mix banana bread
Cake mix muffins
Dump cakes
Holiday dessert bars

It’s a homemaker’s best-kept secret and a lifesaver during busy weeks.

This German chocolate cake isn’t just a recipe. It’s a little love letter I bake every year for someone I love. It’s nostalgic, comforting, and so easy. Whether you’re baking it for a birthday, a holiday gathering, or just a Tuesday night treat, I hope it becomes a favorite in your kitchen too! Hugs!