Baking Sense

The Art And Science of Baking

Blueberry Crumb Cake – Blueberry Buttermilk Coffee Cake

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Blueberry Crumb Cake! Soft blueberry buttermilk coffee cake crowned with brown sugar crumb topping. It’s all about that perfect crumb topping!

a Blueberry Crumb Cake on a cake stand

As I’ve mentioned in previous posts, after years of thinking about, baking, decorating and delivering cakes for a living about the last thing I want to bake and eat at home is cake.

But crumb cake is another thing all together. Even though I’m a little sick of cake, I love the combination of a light and soft buttermilk cake under a chunky topping of  brown sugar  and cinnamon crumbs.

Let’s face it, it’s all about the crumb topping! Folding fresh blueberries into the batter and layering more berries into the crumb topping takes this treat into another league altogether.

This is a cake even I look forward to eating. It’s great for dessert or with a cup of tea, but you could also have it for breakfast or brunch on the weekend.

a blueberry patch

This is the blueberry patch at the farm. The netting keeps the birds out.

Tips for making a great Blueberry Buttermilk Coffee Cake:

  • For this recipe I knew I wanted to use a buttermilk cake for the base layer. Buttermilk is a fantastic baking ingredient. Not only does it add moisture and a nice tangy flavor to a recipe, buttermilk is acidic so it tenderizes the cake crumb.
  • You’ll notice that there is no baking soda in the recipe, only baking powder. Baking soda is on the base side of the pH scale, so it’s used with acidic ingredients to balance the pH of a batter. I purposely did not use baking soda because I wanted to keep the batter slightly acidic. This is one of the softest cakes you’ll ever taste. It absolutely melts in your mouth.
  • The key to a good crumb layer is to mix softened butter into the dry ingredients until it looks exactly like wet sand. When you grab a handful of the mixture it will clump together. By adding the crumb topping in chunks you’ll get nice big crumbs in each mouthful of cake.
  • I used fresh blueberries for this cake, but you could certainly use frozen berries. Don’t defrost them first. You should fold them into the batter while they’re still frozen so they don’t break down and turn the entire cake green.

Scroll through the step-by-step photos to see how to make Blueberry Crumb Cake from scratch:

a bowl of crumb topping

The crumb topping should look like sand and form a clump when squeezed

a bowl of brown sugar crumb topping

Gather the crumb topping into large chunks and set aside while you mix the batter

cake batter with blueberries in a square pan

Dot blueberries on top of the batter before adding the crumb topping

a hand sprinkling crumb topping onto a cake

Break the large clumps of topping into smaller clumps from pea sized to the size of a marble

a Blueberry Crumb Cake

Do you have a favorite blueberry dish you’d like to learn how to make or to perfect? Let me know in the comments below. I’d be happy to do the research and testing and then post the resulting recipe.

a slice of blueberry buttermilk coffee cake

If you love this recipe as much as I do, please consider leaving a 5-star review.

Blueberry Crumb Cake

Blueberry Crumb Cake

Yield: 12 portions
Prep Time: 30 minutes
Cook Time: 1 hour
Total Time: 1 hour 30 minutes

I love the combination of a very light and soft cake under a chunky topping of  brown sugar  and cinnamon crumbs. Let's face it, it's all about the crumb topping and the blueberries!

Ingredients

Crumb Topping

  • 1 1/2 cups (6.75 oz, 189g) cake flour
  • 2/3 cup (6 oz, 168g) light brown sugar
  • pinch of salt
  • 2 teaspoons cinnamon
  • Zest of 1/2 lemon
  • 1 stick (4 oz, 112g) softened unsalted butter, cut into 1" pieces

Cake Batter

  • 1 large egg plus 1 yolk
  • 1/2 cup (4 oz, 120ml) buttermilk, divided
  • 1 1/2 cups (6.75 oz, 189g) cake flour
  • 3/4 cup (6 oz, 168g) granulated sugar
  • 1 1/2 teaspoons baking powder
  • 1/4 teaspoon salt
  • zest of 1/2 lemon
  • 1 stick (4 oz, 112g) butter, softened and cut into 1" pieces
  • 1 pint fresh (or frozen) blueberries

Instructions

  1. Preheat the oven to 350°F. Butter and flour an 9" square cake pan. Cut an 8"x16" piece of parchment paper and line the pan in one direction, leaving a short overhand on each side. Butter and flour the parchment.

Crumb Topping

  1. Combine the flour, brown sugar, salt, cinnamon and zest. Mix on low speed until completely combined. With the mixer running, add the butter and continue to mix until the topping looks like sand. Remove from the mixer and transfer to a small bowl by squeezing handfuls to create large clumps. Set aside while you mix the batter.

Batter

  1. Combine the egg, yolk and 1/4 cup of the buttermilk in a small bowl and set aside.
  2. Sift together the flour, sugar, baking powder and salt. add the zest. With the mixer running on low speed, add the butter and the remaining 1/4 cup of buttermilk. Mix until completely combined. Scrape the bowl and beater. Mix on medium speed for 2-3 minutes to lighten the batter.
  3. Scrape the bowl and add the egg mixture in two batches, scraping between additions. By hand, fold about 2/3 of the blueberries into the batter. Spread the batter into the prepared pan.
  4. Sprinkle 1/2 the remaining blueberries over the top of the batter. Sprinkle 1/2 the crumb topping over the batter, breaking the topping into pea to marble sized clumps. Sprinkle the rest of blueberries and then the remaining crumb topping.
  5. Bake until a toothpick inserted in the center comes out clean, about 40-45 minutes. Cool at least 30 minutes in the pan. Use the parchment to carefully lift the cake out of the pan.
  6. Cool completely on a wire rack

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© Eileen Gray
Cuisine: baked goods / Category: Cakes/Cupcakes

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Blueberry & Cherry Shortcakes
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Blackberry Buttermilk Pie

Reader Interactions

Comments

  1. I tried making this a few days ago and can’t wait to make it again! It was a little more involved than my normal recipes where everything pretty much gets dumped and mixed into one bowl. But the extra effort was soooo worth it! I actually messed up the recipe by using a whole stick of butter in the batter. So I ended up putting it back into the oven a few times because it was still raw in places. I couldn’t stop nibbling on the cooked parts while waiting for it to finish cooking though, so it wasn’t very pretty in the end (and about half gone too!). The cake was unbelievably moist and was the perfect texture. This is the best crumb cake I’ve ever had! I was hoping it would be similar to the Starbucks coffee cake but this was so much better!

    How do I change out the blueberries for a cinnamon (like coffee cake) version? What are other good variations on it in case I’m out of blueberries? I LOVE this recipe! I also love how you do so much testing and your explanations of techniques and why things do/don’t work. That must be unbelievably time consuming. Thank you so much for sharing your hard work!

    Reply

    • Hi Ceeny! Thanks for visiting my blog and for trying the recipe. I’m glad you think it was worth the effort!

      This cake does take kind of long to bake. I used a straight-sided, square 8″ pan. If your pan was a different shape or size it could affect the baking time. Whatever pan you use, the cake batter should come just 1/2 way up the sides of the pan. If you have too much batter just use the extra in a smaller pan or make a few muffins.

      Variations: You could just bake it without the blueberries for a plain crumb cake. You could add a teaspoon or so of cinnamon with the dry ingredients for a cinnamon cake. Do you mean you’d like to have a cinnamon swirl or ripple in the cake? I’d have to try it, but my first thought would be to put 1/2 the batter in the pan, sprinkle a layer of cinnamon sugar over that batter and then put the remaining batter and then the crumb topping in the pan. If you try it let me know how it works. You can also fold in raspberries, cranberries or chunks of fruit (like peach) if you have those on hand instead of blueberries.

      I’m sure in the future I’ll do other versions of crumb cake. I think an apple cinnamon version would be good for fall.

      Reply

      • Ah, yes. Maybe it was my pan that affected my baking time. I used a glass 8″ square pan. I think my oven also heats lower than the setting. I haven’t baked many cakes in this oven and I did have another cake that didn’t brown recently. It also had some under-cooked spots in it.

        I have some round heavy metal cake pans, so I will try one of those next time and add 15 degrees to my oven temparature too. I like your cinnamon swirl idea. And apples with it….yum! Maybe fall will have to come sooner for me. 🙂

        Reply

        • Not only does the size and shape of the pan affect the way it bakes, but definitely glass will bake differently than metal. Glass is a poor conductor of heat so there’s a good chance that’s why it took longer to bake. The glass pan will take longer to heat up in the oven than a aluminum cake pan would. So of course if the pan takes longer to heat up it takes longer to get the heat to the batter in the pan.

          If it was clear glass you will get a nice brown crust on the bottom because the clear glass allows for the radiant heat to brown the bottom and sides of the cake while it bakes. If you try the recipe in a metal cake pan you may not need to increase the oven temp since it’ll conduct heat better than the glass will anyway.

          This reminds me what a difference the pan you bake in can make. I’ll work on a blog post all about baking pans and how the different materials can affect the baking process. Thanks so much for the feedback and taking the time to comment. Eileen

          Reply

    • Hi Christelle, I think you could probably bake it in a skillet. Just be aware that a cast iron skillet will bake much hotter so the cake will brown more. You might have to play with the oven temperature based on the material of the skillet. Let me know how it turns out if you try it. Happy Baking!

      Reply

  3. Hi Eileen,

    I LOVE this recipe. But I recently moved to Thailand where kitchens don’t have ovens and….help! I have a large toaster oven where I can’t really get an exact temperature and I bake by trial and error. So far I’ve successfully baked some cookies. I’ve also baked some simple cakes/brownies using my 8″ square nonstick dark metal pan. This was my first attempt at baking a cake using sifted cake flour. The cake turned out fine, but the crumb topping just melted into the cake! That’s my favorite part! Then the top started getting too browned before the cake was done, so I turned the temperature down and put foil over the top to keep it from burning. I ended up having to bake it almost twice as long. Do you have any ideas on what I can do? I also have a cupcake pan if that would help (same dark non-stick coating). Also, can I just bake the crumb topping by itself and add it to my other cake for now? It has been quite a challenge learning to bake in a toaster oven. I miss my real oven!

    Reply

  4. Hi Ceeny. I’ve never actually owned or baked in a toaster oven. Is the heat source at the top or bottom of the oven? If it’s coming from the top I think baking a cake will be a challenge.

    Reply

  5. I guess you can’t turn off the top element. If you could that would certainly be better. If you can’t turn off the top element I would try a slightly lower temperature. Cover the pan with aluminum foil with the shiny side up to try and deflect some of the heat away from the top of the cake. If there is more than one shelf you might even put a sheet pan on the shelf above the cake to block the heat from the upper element. Good luck.

    Reply

  6. wow. you were right. the cake literally just melts in your mouth. it is so light and fluffy and the flavor with the blueberries is delicious.
    I have tried NY crumb cakes twice before (two different recipes) and both failed! the crumb always sank to the bottom. :0(
    this one did not. it was perfect in every respect.

    thank you!!

    Reply

    • Hi Naleema? Are you based in the US? Cake flour is sold here in the US and is flour made with soft wheat with a lower protein content. It’s good for making cakes, biscuits and other baked good with a soft crumb.

      Reply

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