Caramelized walnut cake

Soft and fluffy walnut cake layers with delicious vanilla and caramelized walnut filling.

Caramelized walnut cake or Hedgehog cake (as the name stands in my mothers cookbook). This is the cake my mother make every Christmas/New Year’s holidays. She make it as a roll cake and call it The Hedgehog cake. This is one of her recipes I love the most. And this year I decided to make it as a layer cake.

Although I had to make some changes to the recipe, the taste is identical as her cake. Her filling has totally different texture it’s more liquid and wouldn’t work as a filling for layered cake, so I made my own buttercream with the same ingredients.

I have found my new obsession. As I wrote in a Chocoate Coconut Cake recipe post, I haven’t had neither one recipe for layer cake until few weeks ago, and I figured out how I actually enjoy making layer cakes. Although they are time consuming, and since I’m a mom to a 9 months old baby it takes me 2 days for one cake, but there is something in that I-can’t-wait-to-see-a-slice-of-that-cake thing.
So, from now on, I decided to make at least one layered cake every month.

What you will need?
For the cake: eggs (white and yolks separated), sugar, flour, ground walnuts, baking powder and pinch of salt.
For the filling: milk, vanilla pudding powder (cook and serve kind for 2 cups milk), cornstarch, sugar, vanilla extract, and caramelized walnut butter (it’s really not hard to make it).
And for caramelized walnuts: sugar and walnuts halves.

For caramel: sugar, water, butter, heavy cream and vanilla. Or use Carnation store-bought caramel (that’s what I used). I used caramel mostly for decoration but it gives more flavor to the cake, but you can omit it and sprinkle the whole cake with chopped caramelized walnuts.

First we have to make caramelized walnuts. Prepare a medium bowl greased with butter or oil (we need it greased so that caramelized walnuts don’t stick to the bowl). Add sugar in a large heavy bottom pan and let it melt on medium low heat, stirring occasionally. When sugar is melted, and starts to get golden color, add walnuts and with a wooden spoon mix everything, so that walnuts are coated in melted sugar. Continue cooking and mixing for few minutes until sugar is brownish and start to smell like caramel. Carefully transfer to a prepared greased bowl and let it cool completely.

For caramel (if using), place sugar and water into a medium saucepan and stir to combine. Cook over medium high heat and stir constantly until the sugar has dissolved and the mixture starts to bubble just a little. Increase a heat and bring to a boil, do not stir anymore.
Let the mixture continue boiling until it turns an amber color. Remove from the heat and slowly whisk in the heavy cream.The mixture will bubble up quite a bit and boil. Then add butter and vanilla, return to heat and constantly mixing bring to a boil. Cook 1 minute, whisking constantly. Remove from heat and let cool to room temperature. Transfer to a container and place in fridge to thicken.

For the cake, separate egg yolks and egg whites. In a bowl, whisk flour, ground walnuts and baking powder. With an electric mixer beat egg whites with salt until stiff peaks form. In a separate bowl beat egg yolks and sugar until pale and frothy. Carefully fold in egg yolks mixture into beaten egg whites. Add dry ingredients and using rubber spatula gently mix until everything is incorporated. Divide batter between 3-20 cm (8 inch) springform pans (bottom lined with parchment paper, sides greased and floured) and bake 10-15 minutes (I baked mine 13 minutes)  on 180 C (350 F).

For the buttercream, there are two options and both work well, only the texture is different. Divide cooled caramelized walnuts in half. First option is to finely ground one half of caramelized walnuts and finely chop the second half (will use this half for sprinkling and decoration) – this is how my mom makes the filling. What I like to do, to get more smoother filling is to put first half of caramelized walnuts into a food processor and process until buttery texture is formed (it won’t be completely smooth, there will be still bits of caramelized sugar and that’s ok) and finely chop the 2nd half. It’s up to you.

Next, pour milk (leave about 5 tablespoons) in a large saucepan and on medium heat bring to a light boil. In the meantime rest of the milk (5 Tbsp) mix with vanilla pudding powder, sugar, cornstarch and vanilla extract. Pour mixture into hot milk and cook, stirring constantly, about 3-4 minutes until thick. Leave it to cool. Beat butter until creamy and smooth and mix into a cooled pudding. Add in caramelized walnuts (finely ground or in buttery form) and mix everything until fully incorporated. Divide the filling in 3 parts.

To assembly. Put one cake layer on the cake stand or platter.Spread one part of filling and cover with second cake layer. Than again filing and third cake layer. With rest of the filling cover entire cake, top and sides.
If you decided to use caramel (if caramel has thickened too much, microwave in 5-10 seconds intervals until it’s pourable (but not warm)) spread it over the top and using a teaspoon make drips on the sides of the cake, sprinkle the top with chopped caramelized walnuts, or if you decided to omit caramel, sprinkle the whole cake, top and sides with chopped caramel walnuts (this is how my mom do it).

Hope you will enjoy this cake as much as we do.

Happy baking, Mihaela

Print Recipe

4.75 from 8 votes

Caramelized walnut cake

Soft and fluffy walnut cake layers with delicious vanilla and caramelized walnuts filling.

Prep Time1 hr

Cook Time25 mins

Total Time1 hr 25 mins

Course: cake

Servings: 10

Author: Mihaela K. Sebrek

Ingredients

For caramelized walnuts:

• 200 grams granulated sugar (1 cup, 7.05 oz)
• 200 grams walnuts halves (7.05 oz)

For the cake:

• 7 eggs whites, and yolks separated
• 100 grams all-purpose flour (3/4 cup,3.53 oz)
• 100 grams ground walnuts (1 cup, 3.53 oz)
• pinch of salt
• 1 teaspoon baking powder
• 120 grams granulated sugar (4.2 oz)

For the filling:

• 500 ml milk 2 cups+1 Tbsp
• 1 vanilla pudding powder (cook and serve type, not instant, for 2 cups of milk), I use dr. Oetker
• 20 grams cornstarch (2 Tbsp, 0.7 oz)
• 70 grams granulated sugar (1/3 cup, 2.47 oz)
• 1 teaspoon pure vanilla extract
• 250 grams butter (1 cup+1 Tbsp, 8.8 oz) room temperature
• caramelized walnut butter or ground caramelized walnuts recipe follows

For caramel (if using):

• 100 gramsgranulated sugar (1/2 cup)
• 30 ml water (2 Tablespoons)
• 75 ml heavy cream (1/4 cup+1 Tbsp) room temperature
• 60 grams butter (1/4 cup) room temperature
• 1 teaspoon vanilla extract

Instructions

Caramelized walnuts:

• Prepare a medium bowl greased with butter or oil (we need it greased so that caramelized walnuts don't stick to the bowl).
• Add sugar in a large heavy bottom pan and let it melt on medium-low heat, stirring occasionally.
• When sugar is melted and starts to get a dark golden color, add walnuts and with a wooden spoon mix everything so that walnuts are coated in melted sugar.
• Continue cooking and mixing for few minutes until sugar is a dark amber color and start to smell like caramel.
• Carefully transfer to a prepared greased bowl and let it cool completely.

For caramel (if using):

• Place sugar and water into a medium saucepan and stir to combine. Cook over medium-high heat and stir constantly until the sugar has dissolved and the mixture starts to bubble just a little. Increase heat and bring to a boil, do not stir anymore.
• Let the mixture continue boiling until it turns an amber color. Remove from the heat and slowly whisk in the heavy cream. The mixture will bubble up quite a bit and boil. Then add butter and vanilla, return to heat and constantly mixing bring to a boil. Cook 1 minute, whisking constantly. Remove from heat and let cool to room temperature. Transfer to a container and place it in the fridge to thicken.

For the cake:

• Preheat oven to 180 C (350 F).
• Prepare 3-20 cm (8-inch) springform pans, bottom lined with parchment paper, sides greased and floured.
• Separate egg yolks and egg whites.
• In a bowl, whisk flour, ground walnuts, and baking powder. With an electric mixer beat egg whites with salt until stiff peaks form. In a separate bowl beat egg yolks and sugar until pale and frothy. Carefully fold in egg yolks mixture into beaten egg whites. Add dry ingredients and using a rubber spatula gently mix until everything is incorporated. Dived batter between 3-20 cm (8-inch) springform pans and bake 10-15 minutes (I baked mine 13 minutes).

For the buttercream:

• There are two options and both work well, only the texture is different.
• Divide cooled caramelized walnuts in half.
• The first option is to finely ground one-half of caramelized walnuts and finely chop the second half (will use this half for sprinkling and decoration) - this is how my mom makes the filling.
• What I like to do, to get more smoother filling is to put the first half of caramelized walnuts into a food processor and process until the buttery texture is formed (it won't be completely smooth, there will be still bits of caramelized sugar and that's ok) and finely chop the 2nd half. It's up to you.
• Next, pour milk (leave about 5 tablespoons) in a large saucepan and on medium heat bring to a light boil.
• In the meantime rest of the milk (5 Tbsp) mix with vanilla pudding powder, sugar, cornstarch, and vanilla extract.
• Pour mixture into hot milk and cook, stirring constantly, about 3-4 minutes until thick.
• Leave it to cool. Beat butter until creamy and smooth and mix into cooled pudding. Add in caramelized walnuts (finely ground or in the buttery form) and mix everything until fully incorporated. Divide the filling into 3 parts.

To assembly:

• Put one cake layer on the cake stand or platter.
• Spread one part of filling and cover with the second cake layer.
• Than again filing and third cake layer. With the rest of the filling cover entire cake, top and sides.
• If you decided to use caramel (if caramel has thickened too much, microwave in 5-10 seconds intervals until it's pourable (but not warm)) spread it over the top and using a teaspoon make drips on the sides of the cake, sprinkle the top with chopped caramelized walnuts, or if you decided to omit caramel, sprinkle the whole cake, top and sides with chopped caramel walnuts (this is how my mom do it).
• Refrigerate for at least 2 hours before serving and slicing.

Tried this recipe?Tag @mihaela_biteitquick on Instagram! I would love to see what you've baked!