Fudgy Nutella Brownies

These Nutella brownies feature a thick, solid slab of chocolate-hazelnut spread frozen and baked right into the center, surrounded by a dense, fudgy dark chocolate brownie. Freezing the spread first keeps it from blending into the batter, so every slice reveals a clean, molten layer of chocolate-hazelnut in the middle. The brownie batter uses coconut sugar for a subtle caramel note, and the recipe works equally well with standard Nutella or a cleaner spread like Artisana if you prefer fewer refined ingredients.

The trick to a defined center is freezing the chocolate-hazelnut spread for at least an hour before assembly. This creates a firm slab that holds its shape between two layers of brownie batter and softens into a gooey, sliceable core while the brownies bake.

What makes these Nutella brownies different?

Instead of swirling the spread into the batter, this method freezes it into a single slab and sandwiches it between two layers of chocolate batter. The result is a distinct ribbon of chocolate-hazelnut in every square, surrounded by rich, dark brownie on all sides. The batter is lightly reduced in refined sugar and can be made gluten-free using 1:1 gluten-free flour.

Ingredients

1 ½ cups chocolate-hazelnut spread (Nutella or a cleaner alternative)
½ cup unsalted butter, melted
1 cup dark chocolate chips (melted into butter)
2 large eggs
1 cup coconut sugar or granulated sugar
2 tbsp dark cocoa powder
1 tsp vanilla extract
¼ cup gluten-free flour (or all-purpose)
½ cup dark chocolate chips (folded in, optional)

What each ingredient does

Chocolate-hazelnut spread

Choose your preferred spread; both standard Nutella and cleaner alternatives work. Freezing the spread makes it firm enough to remain a separate layer during assembly and bake into a creamy center.

Melted butter and dark chocolate chips

Melting butter with dark chocolate chips creates a glossy, dense chocolate base that gives the brownies their fudgy texture. Use high-quality dark chocolate for the best flavor. Sugar-free chocolate can be used but may reduce the shiny top crust.

Eggs and coconut sugar

Whisking eggs and coconut sugar vigorously for 2–3 minutes creates a light foam that contributes to the crinkled, shiny top. Coconut sugar adds a gentle caramel note; granulated sugar is a straightforward 1:1 substitute.

Gluten-free flour and cocoa powder

A small amount of flour binds the dense batter. Use equal amounts of all-purpose flour if not gluten-free. Cornstarch can also work as a flour-free alternative. Dark cocoa powder deepens the chocolate flavor.

How to make Nutella brownies, step by step

Line an 8-inch square pan with parchment paper. Spread the chocolate-hazelnut spread into an even layer and set the pan in the freezer for at least 1 hour so the spread becomes solid.

Preheat the oven to 350°F (175°C). Line another 8-inch square pan (or reuse the same pan after removing the frozen slab) with parchment paper if needed.

In a heatproof bowl, combine the melted butter and 1 cup dark chocolate chips. Stir until smooth and fully melted; warm for 10–15 seconds if needed. Set aside to cool slightly.

In a separate mixing bowl, whisk the eggs and coconut sugar vigorously for 2–3 minutes, until the mixture is light and frothy. This step helps form the shiny, crinkled crust.

Whisk the melted chocolate mixture into the egg-sugar foam until combined. Add the dark cocoa powder, vanilla extract, and flour (and a pinch of espresso powder if you like). Mix until just combined. Fold in the extra ½ cup dark chocolate chips, if using.

Pour half of the batter into the prepared pan and spread it into an even layer. Remove the frozen slab of chocolate-hazelnut spread from the freezer and, using the parchment, lift it out and place it gently on top of the first batter layer. Pour the remaining batter over the top, smoothing gently to cover.

Bake for 33–36 minutes, or until a toothpick inserted in the brownie portion comes out mostly clean (a few moist crumbs are fine). Do not overbake — the brownies will continue to set as they cool.

Remove from the oven and let cool completely before slicing so the layers hold together cleanly.

Why freezing the spread makes the center layer work

At room temperature, chocolate-hazelnut spread is too soft and would simply sink into the batter. Freezing it creates a stable slab that won’t sink when you pour the second layer of batter over it. During baking the slab softens and becomes molten while the brownie bakes around it, leaving a distinct center band.

Tips for the best result

Freeze for the full hour

Make sure the spread is fully firm before assembly. If it still feels pliable, return it to the freezer for an additional 15–20 minutes.

Whisk eggs and sugar for the full 2–3 minutes

Vigorous whisking creates the foam that yields the shiny, crinkled top. Rushing this step gives a flat, matte surface.

Do not overbake

Remove the brownies when the toothpick is mostly clean. A perfectly clean toothpick usually means overbaked, dry brownies.

Use high-quality dark chocolate chips

A good dark chocolate makes the biggest flavor difference. Sugar-free chips can be substituted, but they may reduce the shiny crust.

Substitutions

Original	Substitute	Notes
Artisana spread	Standard Nutella	Same amount; both work
Gluten-free flour	All-purpose flour	Direct 1:1 swap
Gluten-free flour	Cornstarch	Flour-free option, slightly denser
Coconut sugar	Granulated sugar	1:1 substitute; less caramel flavor
Dark cocoa powder	Regular cocoa powder	Slightly less intense chocolate

Storage

Room temperature: Store in an airtight container for up to 3 days. The chocolate-hazelnut center remains soft and gooey.

Freezer: Wrap individual brownies tightly and freeze for up to 3 months. Thaw at room temperature for 30–45 minutes before serving.

Frequently asked questions

Can I use regular flour instead of gluten-free flour?

Yes. All-purpose flour is a direct 1:1 substitute. Cornstarch can be used for a flour-free version but produces a slightly denser texture.

Do I have to freeze the chocolate-hazelnut spread?

Yes. Freezing the spread keeps it from sinking into the batter and allows it to become a distinct, gooey center after baking.

Can I use white granulated sugar instead of coconut sugar?

Yes. Use a 1:1 substitution. You’ll lose the caramel undertone from coconut sugar, but the brownies will still be delicious.

Why is my top crust not shiny?

Insufficient whisking of eggs and sugar is the most common cause. Also, using sugar-free chocolate reduces the sugar-egg interaction that creates the shiny, crinkled top.

Can I freeze these brownies?

Yes. Wrap individual pieces tightly and freeze for up to three months. Thaw at room temperature before enjoying.