02 October 2012

Diós Torta or Walnut Torte with Walnut Custard Buttercream

Out of town guest?  Time to bake.

House guests are always a great excuse for me to try something new.  The way I see it:  I'll provide the shelter if you'll be my guinea pig.

I pulled the Kaffeehaus book off the shelf and rather than choosing a recipe, I let the book fall open to a page and that's how I landed on the Hungarian Diós Torta.


Sounded delicious and possibly nutritious. Walnuts are really good for you, right?

Diós Torta is in the 'Fancy Cakes' chapter of The Book.  I'm guessing it falls under that category because nuts can be pricey.  It may look impressive or "fancy," but don't be fooled, it's not difficult to make.

Walnuts show up a lot in Hungarian desserts.  I don't know if it's because of the historical connection to Turkey or just that the walnuts grow like weeds in Hungary.  In this recipe they are ground, but not with a food processor, by hand with a nut grinder.  Apparently, this retains the walnut's fluffy texture.  It was news to me that nuts could be fluffy, but after making the torte I now understand about the fluffiness.  Now I have another useful factoid to file away in my baking brain.

What Happened:
How to grind nuts without using a food processor?

I don't own a nut grinder.  My MacGyver instinct kicked in and I thought to try my rotary cheese grater.  Walnuts are pretty soft, so just maybe....

I'm happy to report it worked.  Messy and a bit of a pain, but I had hand-ground walnuts.

For comparison I also ground a small amount in my processor.  Rubbing the two samples between my fingers, the hand-ground nut really did feel fluffier.

I think the difference is that the speed and heat of the  processor blade tends to compact the nuts.  The blade heat forces too much of the nut's oil to be released creating a more "pasty" ground walnut, but only by comparison to the hand-ground ones.

Grinding by hand is slower and doesn't generate the same heat leaving the walnut (and its oil) more intact in effect making a mini, mini, mini nut that structurally more closely resembles the whole walnut.  

Presumably, the fluffier nut would make a difference in the texture of the cake, but if you don't have the patience to MacGyver it, then by all means grind your walnuts in the food processor--carefully. Only the fussiest of the fussy would be able to tell the difference.

Grinding the nuts--that was the only really challenging part of this recipe.

Something did happen with the baking of the cake though. After coming out of the oven it sunk slightly. WHAAA?

Don't panic if this happens.

It's no big deal--not ideal, but seriously no biggie. This can happen with the delicate structure of foam cakes.  I pulled it out of the oven probably about 3 minutes too soon.  While it was done by the toothpick-in-the-center test, the structure hadn't entirely set. It didn't effect the flavor or texture of the cake in any way.  The only consequence was that my layers weren't pristine--oh well, it happens.  So when you think the cake's done, wait 2 minutes and then pull it out.

Walnut buttercream.  In a word: Yum!

I didn't use it all so I froze what was left over thinking it would be really great on a chocolate cake with a little apricot preserves or orange marmalade smeared on the cake layers. I love leftover dessert inspirations.

Things I Would Change:

  • A touch of acid could do this cake a huge favor.  I added orange zest to the recipe to give it a little lilt.  It's a natural fit with walnuts and should serve to complement the play between the nuts and the cream.  Another way to balance the taste would be to slather a thin coating of tart preserves of any flavor between the two layers.
  • Toast the nuts.  With enough prep time this could only improve on what already works. Definitely gilding the lily.

The Results:
Pretty tasty.  OK, very tasty.

Cody's comment was, and I quote, "nutty."  I sure hope so!

The nuts made for a big flavor and added considerable moistness to the cake. Even with the custard-based buttercream it was surprisingly light. My house guest seemed to enjoy my experiment too.  You never know who is really up for trying something new and she was absolutely on board.

To be clear, this isn't one of those tall, sugary butter cakes that you see at birthday parties or anniversaries, this is more the low-slung, elegant, after-dinner variety that screams for a coffee chaser.  Now that Fall is here, I think this Diós Torta should sneak its way onto your table some night soon.  Don't forget the coffee!

Diós Torta
12 servings
adapted from Rick Rodgers Kaffeehaus
1/3 c   dried bread crumbs, for the pan
1 c       walnuts (4 ½ oz)
1 c       flour
7          eggs, room temperature
¾ c     sugar
1 T        orange zest (optional)

2 c       walnuts, chopped (8oz)
1 ¼ c  powdered sugar
1 c       milk
2 T        cornstarch
2          egg yolks
2 T        golden rum
1 t        vanilla
1 ½ c  butter, at cool room temperature

½ c     walnuts, finely chopped (2 oz)
12        walnut halves

Preheat oven to 350 degrees and place a rack in the center of the oven.

Lightly butter a 9-inch springform pan.  Dust with bread crumbs and tap out the excess.  Line the bottom of the pan with a round of parchment.

Grind the nuts in a rotary nut grinder fitted with the fine grating drum.  Transfer to a bowl and mix with the flour and orange zest, if using.  (Although it will yield different results you could gently pulse the nuts and the flour together in a food processor until the nuts are ground.)

Beat the eggs with the whisk attachment in the bowl of a stand mixer at high speed.  After the eggs have gotten foamy, lower the speed and add the sugar in a slow, steady stream.  Increase the speed to high and continue to beat for 15 minutes.  The eggs will reach a ribbon stage where they are stiff and 3 times their volume.

In two additions, fold in the flour walnut mixture with a spatula or large balloon whisk.  Spread evenly in the pan.

Bake until a toothpick inserted into the center of the cake comes out clean, about 35 to 40 minutes.  Do not under bake, the cake will sink.  Cool in the pan for 5 minutes.  Remove the ring and invert the cake onto a wire rack.  Remove the parchment paper and reverse on another rack to cool completely.
For the buttercream:  Process the walnuts and powdered sugar in the bowl of a food processor until the walnuts are almost a powder scraping the corners of the bowl as necessary.

Pour the milk into a medium saucepan.  Sprinkle in the cornstarch and whisk until dissolved.  Whisk in the yolks.  Cook over medium-low heat, whisking constantly, until the custard is thick as a pudding.  The eggs won’t curdle because of the cornstarch.  Strain the custard into a medium bowl set over an ice bath.  Stir in the rum and vanilla.  Let stand until cool, stirring occasionally.

Transfer the custard to the bowl of a standing mixer.  Using the whisk attachment, beat until smooth, about 1 minute.  On medium speed, drop in the soft (not oily) butter in a couple of tablespoons at a time.  Increase the speed as needed to make sure the cream is smooth.  Beat in the walnut sugar mixture.  Cool the buttercream in the ice bath or refrigerator if it’s too warm to spread.

To assemble:  Transfer ¾ cup of the buttercream to a pastry bag fitted with a star tip (make sure the star is open and not closed in order to accommodate the walnuts in the buttercream).  Using a large serrated knife slice the cooled cake in half horizontally, creating 2 equal layers.

Place the bottom cake layer on an 8-inch cake round.  Spread the layer with about 1 cup of the remaining buttercream.  Top with the second cake layer and frost the top and sides with the remaining buttercream.  Press the chopped walnuts onto the side of the cake.  Pipe 12 rosettes on top of the cake and place a walnut half on each.  Refrigerate until 1 hour before serving.  Cake keeps well for 2-3 days.


  1. How fine are the nuts ground? Not as fine as nut "meal" or ground almonds that can be found sold in stores?

  2. This recipe is nothing like what I learned as a teenager from my Hungarian aunt. But I have even modified her recipe, creating a gluten-free cake. Instead of flour or breadcrumbs, I use ground almonds. Lemon zest rather than orange. The egg yellows are combined with the sugar; the whites are beat separately and folded in as the last task before baking. I also don't grease the pans; I use parchment paper on the bottom and a knife to separate the cake from the spring-form pan. Finally, I invert the freshly baked torts onto a cooling rack. This helps to avoid that sinking feeling.

  3. Beautiful cake and the orange zest would put it over the top. Will absolutely be adding that. I love walnuts so this is getting on my to do list right now!