World Nutella Day: A Hazelnut Cake with Chocolate-Dipped Florentines and Nutella Mousse

Happy Nutella Day!

I love Nutella.  A friend once told me that my slogan should be "Life is Better With Nutella."  I use it to fill macarons, to decorate cupcakes, to flavor pastry cream, to enliven ganache or frosting... there are so many possibilties.  But this Nutella mousse is one of my favorite (and easiest!) Nutella recipes.  Here it is as the filling for my favorite yellow cake.

The cake, however, is not so easy.  The frosting alone took me over two hours, though that includes the time it took to skin the hazelnuts and make homemade praline.  If you're in the mood to spend a few cozy evenings in the kitchen with your mixer and your oven though, it's totally worth it.  If not, just make the mousse, and your guests will still be smitten.

For more Nutella recipes, see the World Nutella Day Website; World Nutella Day is sponsored by Ms. Adventures in Italy and Bleeding Espresso.

 

Hazelnut Genoise Cake (adapted from Carole Walter)

1 1/2 cups hazelnut flour (finely ground hazelnuts)
2/3 cup cake flour
2 tablespoons cornstarch
1/8 teaspoon salt
5 large eggs, separated
2 large yolks
1 cup sugar, separated
1 teaspoon vanilla
1/2 teaspoon lemon zest
1/4 cup warm brown butter

Preheat oven to 350F.   Spray 3 8" cake pans with baking spray, line with parchment, and spray again. 

Whisk together the hazelnut flour, cake flour, cornstarch, and salt; set aside.  

Beat the 7 egg yolks until thick and light in color, about 3-4 minutes.  Add 3/4 cup sugar very slowly, beating another 3-4 minutes.  Beat in the vanilla and lemon zest on low.

Beat the 5 egg whites to soft peaks.  Slowly add the remaining 1/4 cup sugar, and beat for another minute.  Whisk in the yolk mixture, whisking for one minute.  Gently and quickly fold in all but 2 tablespoons of the flour mixture, a couple of tablespoons at a time.  Pour the warm brown butter over batter, and gently fold.  Fold in the remaining 2 tablespoons of flour mixture.  Pour into pans, and bake for 15-20 minutes until a toothpick just comes out clean.  Cool in pan for about 5 minutes, then flip over onto greased cooling rack.

Nutella Mousse (from The Scotto Family)

1 jar (13 ounces) Nutella
1/2 cup mascarpone cheese
1 cup heavy cream
1 ounce Frangelico

Beat together the Nutella and mascarpone on high for several minutes until very smooth.

In a separate bowl, whip the heavy cream and Frangelico to stiff peaks.  Fold cream into the Nutella/mascarpone mixture.  Chill for at least a half hour (longer in warm weather).  If it's very lumpy when you remove it from the fridge, you can beat it for 30 seconds or so to smooth it out. 

 


Frangelico Simple Syrup

1 cup sugar
1/2 tablespoon corn syrup
1/2 cup water

1/4 cup Frangelico (or other liqueur)

In a heavy saucepan, bring the sugar, corn syrup, and water to a boil; set aside to cool.  The syrup can be stored in the fridge for a few weeks, but it's a little too heavy to spread on a cake.  First, we'll dilute it and add some flavoring.

To 1/2 cup of the heavy syrup made above, add 1/4 cup water and 1/4 cup Frangelico.  Stir, and reserve until ready to brush over cake layers.

Hazelnut Praline Paste (you can buy this at some stores, I promise I won't tell.)


This is like nutella without the chocolate. It's great to add to pastry cream, to buttercream frosting, or just to spread over toast!

2 cup hazelnuts, roasted and skinned (as much as possible)
3/4 cup sugar (you can keep it at 1/2 cup if you want to cut the sweetness)

Grind the hazelnuts and sugar in the food processor until the hazelnuts become oily, about 4 minutes.  Scrape down the food processor bowl once or twice.

 Peeling hazelnuts is not fun at all, I can never get the skins all the way off.  I usually get like 10 perfect ones and a bunch with partial skins.  Luckily,  the slight bitterness that the skin adds isn't really noticeable.

 

Ready for Buttercream 

Italian Praline Buttercream Frosting (makes 2 pounds, enough to frost 3 layer 8" cake)

2/3 pound (about 2 1/3 cups) sugar
1/3 pound egg whites (from about 5 large eggs)
1/3 cup water
1 pound (4 sticks) butter, soft
2 teaspoons vanilla extract
4 ounces praline paste

Combine 1/4 of the sugar (1/6 pound or 1/2 cup + 1 tablespoon) with the egg whites in the bowl of a stand mixer.  Whip the mixture with the whisk attachment, first on low, then increasing speed, to soft peaks.

Combine the water with the remaining sugar in a saucepan, and cook until it reaches 240F (soft ball stage).  Immediately, pour the syrup into a warm glass 2-cup measure (it's easier to pour from this than the saucepan).  While the mixer is still running, pour the syrup into the mixer bowl, avoiding the whisk (pour it right at the edge of the bowl and you'll be fine).  Continue whipping until the mixture is room temperature.

While the mixture is cooling and whipping away, cut the butter into small pieces.  It should be very soft but not melted.  When the mixture is room temperature, switch to the paddle attachment, and gradually add the butter on medium speed, beating until the frosting is smooth and light. If the bowl gets too cold, the mixture will curdle (i.e. break).  Don't despair, you can fix it!  A little warmth is usually all it takes.  I hold my mixer bowl over a burner on the stove to warm it up (it's ok if a little bit melts) for a few seconds, and then start mixing again.  Good as new!  

Add the praline paste, and mix until thoroughly combined.

Hazelnut Florentine Close-up

Hazelnut Florentine  (Makes 2 8" Disks; Recipe from CIA)

1/3 cup heavy cream
2 2/3 ounces sugar (just under 1/3 cup)
2/3 ounce (1 1/3 tablespoons) butter
4 ounces hazelnuts, finely ground
1/6 ounce (just under 2 teaspoons) cake flour
3 ounces semisweet chocolate

Preheat oven to 350F.  Trace 2 8" circles on parchment paper, and flip over on baking sheet (so the ink doesn't touch the batter).

Combine the cream, sugar, and butter in a saucepan, and bring to a boil.  Stir in the hazelnuts and flour.  Remove from heat, and spread half the mixture evenly over each disk with an offset metal spatula.  Bake until golden brown, about 18-20 minutes.

When the florentines are set, no longer sticky, but still slightly warm, place an 8" cake board over each disk, and trim the edges using a pizza wheel, creating a perfect disk.  Cut each disk into 8-10 wedges. Let cool completely.

Melt the semi-sweet chocolate in a small bowl, and dip the edge of each florentine about 1/4" into the chocolate.  Lay flat on parchment paper until the chocolate is set.

Assembly

Place one cake layer on a cake board.  Brush with simple syrup.  Top with about 1/4 of the buttercream.  Repeat with other layers.  Cover the sides of the cake with frosting, and smooth with a metal spatula.

Pipe buttercream shells around the base of the cake with a star tip.

Pipe 8 (or however many wedges you cut from the florentine) small balls of frosting equally spaced around the cake, about halfway between the center and outer edge.  Just before serving, lay the florentine wedges on the balls of frosting for support.  If you do this too early, the florentine wedges may start to bend.