Hazelnut Crumble Cake
This weekend, I’ve reached the end of my funemployment traveling and am spending some much-needed time with my college roommate, Cate, her partner, Jonathan, and their corgi puppy, Giles. Cate was a baker before I ever thought to start this blog, and last time I was visiting her I gave her the cookbook Sweet by Ottolenghi, which we baked out of together. At that point in time, we were hosting a brunch and wanted to make a Rum Raisin Cake. I asked Cate if she had everything we needed to make it, and she assured me that she did.
She was mostly right, but forgot about one mildly important tool: a Bundt pan. We ended up making it as a rectangle cake and icing it, which worked, but this time when I visited and we decided to make a cake, I didn’t want to settle for a rectangle again. Most of the cakes in the cookbook are Bundt cakes, and I firmly believe that no kitchen should be without a Bundt pan. I actually have two – a traditional one and one shaped like a gingerbread house. So before starting this cake, I went out and got Cate a Bundt pan, and now they’ll be able to make all sorts of round cakes with a hole in the middle!
Anyways, this cake would be great for a brunch, but we served it as a dessert. Lots of hazelnut flavor, supplemented with some Nutella icing, makes it a certain crowd pleaser.
First, toast and skin the hazelnuts. To do so, place them on a baking sheet and roast for around 12 minutes at 350°F, until they smell nutty. Remove from oven and place in the middle of a clean dish towel or paper towel. Bundle them up and rub them together to remove the skins. Allow the hazelnuts to cool slightly and then place them in a food processor with the sugar, cinnamon, and salt. Process until the nuts are finely chopped and set aside. Cate and Jonathan have a Vitamix, which I learned actually makes for a great food processor if you don’t have access to a Cuisinart.
In a medium bowl, whisk together the sour cream, yogurt, and baking soda. Allow to sit for 15 minutes until it puffs up. Meanwhile, back in the food processor, process the eggs and sugar for about a minute. Add the butter and process for another minute. It will look kind of curdled – that’s normal. You didn’t mess up. Back with the puffed up sour cream mixture, stir in the rum and vanilla extract. Add the mixture to the food processor and pulse to bring the batter together. Pour batter into a large bowl. In a small bowl, whisk together the flour, baking powder, and salt. Add the dry ingredients to the batter and stir until everything comes together. Grease your Bundt pan generously. With all the cracks and crevices, you really want to make sure this cake doesn’t get stuck. Spread about 1/3 of the batter into the bottom of the Bundt pan. Next, spread about 1/3 of the hazelnut crumble evenly over the batter. Repeat with another third of the batter and another third of the hazelnut mixture. Finish off with the remaining batter and remaining hazelnut mixture. With the last layer of hazelnut crumble, press the mixture into the batter to secure it. This will make a nice crust when it’s baking and help it from falling apart when you flip it out of the pan. Bake at 400°F for about 40 to 45 minutes, or until a toothpick comes out clean. Allow to cool 10 minutes in the pan before flipping onto a wire rack to cool completely. When the cake is cool, it’s time to make the icing. To do so, start by putting the Nutella and chocolate into a medium bowl. Heat the heavy cream over medium heat for a couple of minutes, until bubble form around the outside. Immediately pour over chocolate. Let sit for a couple of minutes before stirring with a rubber spatula to make smooth. If the ganache is too watery, add more Nutella or pop it in the fridge for a bit. Drizzle icing over the cake and sprinkle with sliced hazelnuts. Save some icing on the side to serve with cake for people who like all the frosting. Pro tip on the hazelnuts on top. If you slice them, rather than chop them, they will look a little bit prettier. It’s worth the effort. And, when you slice into the cake, you’ll have these great veins of hazelnut crumble!Store covered at room temperature, and continue to eat for breakfast, snacks, dessert, etc.
Enjoy!
Hazelnut Crumble Cake
Ingredients:
Hazelnut Crumble
- 2 3/4 ounces hazelnuts
- 1/3 cup + 2 teaspoon sugar
- 1 1/4 teaspoon cinnamon
- 1/4 teaspoon salt
Cake
- 1 cup + 2 tablespoons sour cream
- 1/2 cup plain greek yogurt
- 1 1/2 teaspoon baking soda
- 3 eggs
- 1 1/3 cups sugar
- 1 cup + 1 1/2 tablespoons butter, softened
- 1 tablespoon spiced rum
- 2 teaspoons vanilla extract
- 3 2/3 cups + 1 tablespoon flour
- 2 teaspoons baking powder
- 1 teaspoon salt
Nutella Ganache
- 3 ounces 60% milk chocolate, chopped
- 1/4 cup Nutella
- 6 tablespoons + 2 teaspoons heavy cream
Directions:
Hazelnut Crumble
- Roast hazelnuts on a baking sheet at 350°F for about 12 minutes, until they smell nutty.
- Remove from oven and place in the middle of a clean dish towel. Bundle up and rub together to remove skins.
- Allow nuts to cool slightly before placing in a food processor with sugar, cinnamon, and salt. Process until nuts are finely chopped. Set aside.
Cake
- In a medium bowl, combine sour cream, yogurt, and baking soda with a whisk. Set aside for 15 minutes to puff up.
- In a food processor, process eggs and sugar for about a minute. Add butter and process for another minute.
- After the sour cream mixture has puffed up, whisk in the rum and vanilla extract.
- Pour sour cream mixture into food processor and pulse until combined. Pour into large bowl.
- In a small bowl, whisk together the flour, baking powder, and salt. Add to batter and stir just until batter comes together.
- Generously grease a Bundt pan. Spread about 1/3 of the batter in the bottom of the pan.
- Sprinkle about 1/3 of the hazelnut crumble over the batter.
- Repeat with another third of the batter and 1/3 of the hazelnut crumble.
- Spread remaining batter over top, and sprinkle with remaining hazelnut crumble. Use a rubber spatula to press crumble into batter to secure it.
- Bake at 400°F for 40 to 45 minutes, until a toothpick comes out clean. Allow to cool 10 minutes in pan before transferring to a wire rack to cool completely.
Nutella Ganache
- In a medium bowl, combine chopped chocolate and Nutella.
- In a small saucepan over medium heat, heat heavy cream for a couple of minutes, until bubbles for at edges. Immediately pour hot cream over chocolate and allow to sit for a few minutes.
- Use a rubber spatula to stir ganache and make smooth. Drizzle over top of cake and sprinkle with sliced hazelnuts.