This viral Chocolate Crunch Cake is every chocolate lover’s dream come true! Soft, moist, fudgy, and topped with the crunchiest layer ever!

About This Recipe

Chocolate crunch cakes are everywhere right now, and honestly… I completely understand the hype. It’s rich, it’s indulgent, and it has that perfect contrast of soft cake + crunchy topping that keeps you going back for “just one more bite.” After seeing so many people make their own versions, I had to create mine, and let me tell you, it did not disappoint.

This recipe is a combination of everything my readers already love: the base is my go-to chocolate cake recipe (yes, the same one from my Matilda Chocolate Cake, aka the most loved recipe on my blog). It uses vegetable oil instead of butter, which makes the cake incredibly moist and tender. Then it’s soaked in a warm chocolate-toffee sauce inspired by my Chocolate Sticky Toffee Pudding. And finally… the star of the show: a thick, crunchy layer of chocolate-covered homemade feuilletine.

What is Feuilletine?

Feuilletine (pronounced foo-yeu-teen) is a super thin, crispy wafer used by pastry chefs to add texture to chocolates, pralines, and layered desserts like entremets. It has a buttery, delicate crunch that doesn’t get soggy easily, and while it sounds fancy, it’s actually incredibly easy to make at home. This recipe takes only about 20 minutes and tastes just like the real thing.

This cake checks every box: soft, fudgy, crunchy, chocolaty, rich, and unbelievably satisfying. Truly the ultimate treat if you love chocolate as much as I do!

What You Need To Make This Recipe

For the Feuilletine

Egg whites
Icing sugar
Vanilla powder or extract
Unsalted butter (melted + cooled)
All-purpose flour

Substitutes:

Vanilla extract can replace vanilla powder.
Dairy-free butter works for a dairy-free feuilletine.

For the Chocolate Cake

All-purpose flour
Granulated sugar
Unsweetened cocoa powder
Baking powder
Baking soda
Salt
Buttermilk
Vegetable oil
Egg
Vanilla extract
Hot coffee

Substitutes:

Hot water can replace coffee (but coffee enhances the chocolate flavor).
Use milk + 1 tsp vinegar if you don’t have buttermilk.
Any neutral oil works.

For the Chocolate Sauce

Unsalted butter
Heavy cream
Brown sugar
Dark or semi-sweet chocolate

Substitutes:

Coconut cream can replace heavy cream.
Light brown and dark brown sugar both work.

For the Crunch Topping

Feuilletine (homemade from above)
Chocolate spread

Substitutes:

Nutella works if you want a hazelnut twist.
Melted milk or dark chocolate can be used, but it will set firmer.

Pro Tips

Make the feuilletine ahead: It stays fresh for up to 4 weeks in an airtight container — super convenient!
Serve the cake fresh: The crunch topping is at its BEST within the first 24 hours. After that, it softens but still tastes amazing.
Too much chocolate? Skip the sauce! The cake stays moist thanks to the oil, even without soaking it.
Spread the batter thin for feuilletine: The thinner it is, the crunchier it becomes.
Microwave the chocolate spread gently: Short intervals prevent burning.

FAQ’s

What does feuilletine taste like?

It tastes like buttery, crispy, caramelized wafers, similar to the crunchy bits inside fancy chocolate pralines.

Can I use store-bought feuilletine?

Absolutely! Use 120g, the same as homemade.

Can I double this recipe?

Yes, bake it in an 8-inch square pan and increase the bake time slightly.

What can I use instead of coffee?

Hot water works fine, but coffee gives a deeper chocolate flavor.

How long does the cake last?

2–3 days in the fridge, but the crunch layer is best on the first day.

If you’re craving a viral-worthy chocolate dessert that’s easy, decadent, and full of texture, this Chocolate Crunch Cake is the one. I can’t wait for you to try it!

And if you love chocolate like I do, you’ll also enjoy:
brown butter chocolate chip cookies, double chocolate pistachio cookies, chocolate fudge cake, chocolate tiramisu cake, and my eggless Matilda chocolate cake.

Chocolate Crunch Cake

This viral Chocolate Crunch Cake is every chocolate lover’s dream come true, soft, moist, fudgy, and topped with the crunchiest layer ever!

Print Recipe Pin Recipe

Prep Time 30

Cook Time 35

Resting Time 10

Total Time 1 15

Course Dessert

Cuisine American

Servings 8 servings

Calories 699 kcal

Equipment

3 Medium-sized mixing bowls
1 Large mixing bowl
2 Spatulas
Kitchen scale or measuring cups
Measuring spoons
2 baking sheets lined with parchment paper
Offset spatula optional
6-inch square cake pan greased
small saucepan
Small microwave-safe bowl for heating chocolate spread
Skewer or toothpick

Ingredients

For the Feuilletine

2 egg whites room temp
77 g icing sugar (2/3 cup, packed)
1 tbsp vanilla powder or vanilla extract
77 g unsalted butter (5 1/2 tbsp) melted & cooled
77 g all-purpose flour (1/2 cup + 1 tbsp)

For the Chocolate Cake

120 g all-purpose flour (1 cup)
200 g granulated sugar (1 cup)
32 g unsweetened cocoa powder (1/3 cup)
1/2 tsp baking powder
1 tsp baking soda
1/4 tsp salt
120 ml buttermilk (1/2 cup) room temp
60 ml vegetable oil (1/4 cup)
1 egg room temp
1/2 tsp vanilla extract
90 ml hot coffee (1/4 cup + 2 tbsp)

For the Chocolate Sauce

30 g unsalted butter (2 tbsp)
150 g heavy cream (2/3 cup)
45 g brown sugar (3 tbsp, packed)
80 g dark or semi-sweet chocolate (1/2 cup) chopped

For the Crunch Topping

120 g feuilletine (~ 2 cups)
125 g chocolate spread (~ 1/2 cup)

Instructions

Make the Feuilletine

Preheat oven to 200°C.
Whisk egg whites, icing sugar, and vanilla until combined.
Add melted butter and mix well.
Add flour and whisk until smooth.
Spread very thinly onto two parchment-lined baking sheets.
Bake for 8–10 minutes or until golden.
Cool completely, it will crisp up as it cools. Then break into small flakes.
Store in an airtight until needed.

Make the Chocolate Cake

Preheat oven to 180°C (350°F) and grease a 6-inch square pan.
In a bowl, mix flour, sugar, cocoa powder, baking powder, baking soda, and salt.
Add buttermilk, vegetable oil, egg, and vanilla, whisk to combine.
Add hot coffee and whisk until smooth.
Pour into the pan and bake for 25–30 minutes or until a toothpick inserted into the center comes out clean.

Make the Chocolate Sauce

While the cake bakes make the chocolate sauce. Add all sauce ingredients to a saucepan.
Heat on medium-low, stirring until everything melts.
Remove from heat.