Brown Butter Blueberry Streusel Cake

More sweet than tart, covered in a beautiful blue skin, blueberries are packed full of antioxidants. Fortunately, they are addictingly tasty too!  Blueberries have started appearing at the farmer's markets here in San Francisco within the last month and are plump and juicy.  It's been a lot of fun to snack on them or to figure out what recipes they can go into.

For pancakes and during the winter, we prefer the little ones from Maine - no bigger than a small pea but with little bursts of flavor and sweetness.  For snacking out of hand, the bigger the better!  When challenged to come up with a recipe featuring blueberries for the U.S. Highbush Blueberry Council, I had a lot of fun (as did my impromptu tasters) coming up with a recipe that was just as delicious for breakfast as it is for tea or for dessert.  Best of all, it combines two great ingredients: blueberries and brown butter.

Brown butter is one of those fun mysteries because of the transformation in flavor that it goes through.  I've only started to play around with brown butter in my baking; previously, I mainly used it in French recipes like sole meunière.

For my cake, you start with browning 10 Tablespoons of butter.  Some things learned along the way: brown the butter in a regular skillet, as you can see the browning action and know when to stop much easier than in a dark nonstick pan.  Another is to brown slowly and gently while keeping a close eye on it, as you have to remember that it continues to brown even after you take it off the heat.  Lastly, immediately scrape the brown butter into another container, or else the solids which contain all the flavor stick to the bottom of the pan and don't end up in your cake batter!  (Don't listen to the people who tell you to strain it!)

Next up was a streusel topping.  As much as I love a thick, crumbly layer of streusel on top of a cake, I kept it to a thin layer so that it didn't overwhelm the blueberries in the cake.

This is one of the cakes that has multiple parts but only takes a few minutes to actually mix together.  It's quite a thick batter, so you don't really have to worry about the blueberries sinking.  You can just fold them in gently at the end and they distribute themselves quite nicely.  I like the tiny Maine blueberries in this cake, but of course, go with what's fresh and what you like.  If you can't get fresh ones, don't be afraid of frozen ones, as they work just as well and are just as nutritious.  You don't even have to defrost them, just fold them right in.

And the delicious result?  You decide:

A crisp, crackly top covers a thick, moist cake studded with blueberries.  The brown butter adds a subtle nutty accent and more depth of flavor, the milk keeps the cake tender, and you get hits of sweetness from the swirls of blueberries.  Trust me, it's hard to wait until this cake has cooled before diving in.  We've had it for breakfast, for dessert, and even by stolen forkfuls throughout the day when we thought no one was looking.  I hope you enjoy it as much as I do!

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Brown Butter Blueberry Streusel Cake
Makes one 9" cake

Streusel Topping:
1/4 cup all-purpose flour
2 Tablespoons granulated sugar
2 Tablespoons firmly packed dark brown sugar
1/4 teaspoon ground cinnamon
Pinch salt
2 Tablespoons cold unsalted butter, cut into 4 pieces

Cake:
5 ounces (10 Tbsp) unsalted butter
1 1/4 cups all-purpose flour
3/4 cup granulated sugar
1 teaspoon baking powder
1/4 teaspoon salt
2 large eggs
1/4 cup milk
1/2 teaspoon vanilla extract
1 1/4 cups fresh or frozen blueberries (I prefer the little Maine ones)

1. Preheat the oven to 350°F. Butter a 9-inch cake pan or springform pan and dust with flour, set aside.
2.  Brown the butter: melt in a medium skillet over medium heat and cook it until the butter browns and smells nutty (about 5 - 7 minutes). Swirl the pan occasionally to move the solids around, and you are looking for the solids at the bottom of the pan to turn a golden brown color.  Remove from the flame, scrape into a heatproof bowl and let cool.
3. Combine flour, brown sugar, cinnamon and salt for streusel topping in a medium bowl.  Add butter pieces and rub butter pieces between fingers until topping pieces are about the size of large peas (or you can use a pastry cutter).  Set aside.
4. For cake, whisk together the flour, sugar, baking powder and salt in bowl of standing mixer fitted with the paddle attachment.  In a separate bowl, whisk together eggs, milk, and vanilla extract.
5. Turn mixer on to low.  Slowly pour in egg mixture and mix until all dry ingredients are just moistened.
6. Slowly pour in cooled browned butter and beat over medium speed until smooth.  Remove bowl from mixer and gently fold in blueberries by hand with a plastic spatula.
7. Pour into prepared pan. Sprinkle with streusel topping and bake until the cake is golden brown and springs back to the touch, about 35 – 40 minutes, or a tester comes out clean.  Let cool at least 20 minutes before serving.

Bon Appétit

Comments

[Sancho Pancho]

Wow, that looks delicious! I think I may even take a step out of my comfort-zone to try making it :)

[Andi Szabo]

I made this last night, and it was DELICIOUS! I have never tried the brown butter technique in anything--your pictures were helpful--and it definately added some depth to the flavor. The fresh blueberried really balanced well with the sweetness of the topping. I think this will be a new family favorite!