If you’re someone who loves warm, nutty flavors and decadent, melt-in-your-mouth textures, this Hazelnut Cake is going to be your new favorite bake. It’s tender, rich, and beautifully balanced with deep hazelnut notes in both the cake and the frosting. Topped with a silky-smooth hazelnut penuche glaze, this cozy, comforting dessert brings an elegant twist to classic nutty cakes. Whether you serve it for a special brunch, a fall gathering, or just a quiet afternoon treat, it’s guaranteed to impress.
About The Recipe
This Hazelnut Cake was inspired by my love for all things toasted, buttery, and rustic. I wanted to create a recipe that highlights the nutty warmth of hazelnuts without overpowering the sweetness of the cake. So I started with homemade hazelnut butter—rich, fragrant, and worth every second it takes to blend.
From there, I created a moist and soft cake base using brown sugar, buttermilk, and a generous amount of that fresh hazelnut butter. The result? A cake with a tender crumb and an earthy, cozy flavor that doesn’t feel overly sweet.
But the real magic? It’s in the frosting. Instead of a traditional buttercream, I went with a hazelnut penuche—an old-fashioned brown sugar fudge-style glaze that gets poured over the cake while still warm. It sets into a luscious, slightly firm layer that’s full of brown sugar richness and nutty goodness.
Reasons You Will Love This Hazelnut Cake
Deep, nutty flavor – Made with real hazelnut butter and brown sugar for a warm, earthy sweetness that’s unique and indulgent.
Tender, moist crumb – Thanks to the addition of buttermilk and oil, every bite is soft and never dry.
That hazelnut penuche frosting – Silky, glossy, and rich with brown sugar and hazelnut butter. It sets into the perfect fudgy glaze.
Rustic but elegant – Whether you’re serving this at a holiday table or enjoying it with a cup of coffee, it feels special without being fussy.
Homemade hazelnut butter = next-level flavor – You’ll taste the difference in every bite. And yes, you can absolutely make it ahead!
Simple and straightforward – No layering, no fancy techniques—just good ingredients and a few bowls.
Equipment Needed
Before diving in, here’s what you’ll need for success:
8- or 9-inch square baking pan – The perfect size for this single-layer cake.
Parchment paper – Helps the cake lift out easily after baking.
Mixing bowls – You’ll need a few: one for the batter, one for the frosting, one for hazelnut butter.
Electric hand mixer or stand mixer – For beating the eggs and incorporating the hazelnut butter.
Spatula – For scraping, folding, and smoothing the batter.
Food processor – Essential for making homemade hazelnut butter.
Small saucepan – To make the brown sugar penuche glaze.
Ingredients
For the Hazelnut Butter:
2 cups whole hazelnuts, toasted
For the Hazelnut Cake:
2 large eggs
1 cup (200g) brown sugar
1¼ teaspoons baking powder
⅓ cup (75g) hazelnut butter (from above)
½ cup (90g) canola oil
1 cup (130g) cake flour
½ cup (110g) buttermilk or plain kefir
2 teaspoons pure vanilla extract
½ teaspoon fine sea salt
For the Hazelnut Penuche Frosting:
¼ cup (56g) unsalted butter
⅓ cup (65g) brown sugar
¼ cup (60g) whole milk
⅓ cup (75g) hazelnut butter
1 teaspoon pure vanilla extract
¼ teaspoon fine sea salt
1¾ cups (175g) powdered sugar, sifted
How To Make Hazelnut Cake
Step 1: Make the Hazelnut Butter
Preheat your oven to 350°F (175°C). Spread hazelnuts onto a baking sheet and toast for 10 minutes, shaking the pan halfway through for even roasting. Once warm and aromatic, transfer the hazelnuts to a food processor.
Process the nuts until a paste forms, scraping down the sides as needed. Keep going until you reach a loose, pourable consistency—this may take 8 to 10 minutes. Set aside in a jar (you’ll only need some of it for the cake, and the rest is amazing on toast!).
Step 2: Mix the Cake Batter
Line an 8- or 9-inch square pan with parchment paper and lightly grease it. In a large mixing bowl, beat the eggs and brown sugar together using a hand mixer or stand mixer until pale and frothy—about 2 to 3 minutes.
While beating, slowly drizzle in the oil and continue mixing until fully incorporated. Add the hazelnut butter, vanilla extract, and salt, then mix again to combine.
Sift the cake flour and baking powder directly into the batter. Turn the mixer to low and gradually pour in the buttermilk. Beat just until the batter is smooth and shiny—don’t overmix!
Step 3: Bake the Cake
Pour the batter into your prepared pan and smooth out the top. Bake for 30–40 minutes, or until the top springs back when lightly pressed and a toothpick inserted comes out clean. Let the cake cool completely in the pan before adding the frosting.
Make the Penuche Frosting
Step 4: Prepare the Frosting
In a small saucepan over medium-low heat, melt the butter. Add the brown sugar and whisk to combine. Let the mixture come to a gentle boil and cook for about 2 minutes, stirring occasionally. It should become slightly thick and glossy.
Slowly whisk in the milk and allow it to simmer for another 2 minutes without stirring. Remove from heat and immediately stir in the hazelnut butter, vanilla, and salt.
Now, add the sifted powdered sugar and whisk vigorously until the frosting is smooth and shiny. It will look pourable—don’t worry, it will set beautifully once it cools.
Step 5: Frost the Cake
Pour the warm hazelnut penuche frosting evenly over the cooled cake, using a spatula to nudge it gently toward the edges. It will begin to set fairly quickly and develop a soft, matte finish. Allow it to rest at room temperature or chill briefly to speed things up. Once set, the frosting will form a fudge-like layer that’s firm but creamy to the bite.
FAQ’s and Troubleshooting
Can I use store-bought hazelnut butter?
Absolutely! Just make sure it’s unsweetened and smooth for best results. Homemade does give it that fresh-roasted flavor, though.
Why is my penuche frosting grainy?
Graininess usually happens when the sugar isn’t fully dissolved or if the powdered sugar wasn’t sifted. Whisk well, and always sift your sugar for a silky finish.
Can I bake this in a round cake pan?
Yes, you can bake it in a round 9-inch cake pan or even double the recipe for a layer cake. Just adjust your bake time and test for doneness with a toothpick.
Can I make it ahead of time?
Definitely. This cake holds up beautifully. Bake and frost it a day ahead—just store it covered at room temp or in the fridge.
Decorating Ideas
Top with chopped toasted hazelnuts for extra crunch and visual appeal.
Dust with cocoa powder or powdered sugar for a rustic, elegant finish.
Add chocolate shavings or curls for a little indulgent flair.
Serve with whipped cream or a scoop of vanilla ice cream for the ultimate dessert experience.
How To Store
Room Temperature – Store covered for up to 2 days.
Refrigerator – Keeps well in an airtight container for up to 5 days. Let it come to room temp before serving.
Freezer – Freeze the unfrosted cake wrapped tightly for up to 2 months. Thaw overnight and frost before serving.
And there you have it—an irresistibly moist, nutty, and unique Hazelnut Cake with a silky penuche frosting that sets like a dream. Let me know if you’d like a printable version, cupcake adaptation, or ideas for a chocolate-hazelnut twist!
