Lemon Blueberry Marble Cake

This was a CONGRATULATIONS cake. Mabrook Yusif and Naven! <3 We are beyond excited to welcome a little one into the family.

This cake was a close winner. I would love to make it again because I think I know how to make it better. I was excited about using blueberries and lemon but it was not a crowd pleaser. It reminded everyone of a blueberry muffin. The problem could be solved if the lemon buttercream was sweeter which was unanimously unsweet and very buttery. My fault. But, if I made this again, I would love to do lemon and raspberry. You know it.

Lemon Blueberry Cake Notes:
The cake was soft at room temperature, a bit too dense when chilled. I have finally learned not to put too much milk in cake. They always make you put more than necessary. The batter should be thick - like when you make a boxed cake mix. Don’t water it down too much, it doesn’t need the milk for flavor.

I used 8-10 tablespoons of the blueberry jam for the batter. That's when I could actually taste it. And it was great.

Lemon Buttercream Notes:

I decided to make it into an italian meringue buttercream (only using egg whites) rather than a french buttercream (using the yolks) because I didn't want to get anyone sick. Turns out this cake probably needed that extra richness in the frosting (which the yolks would have provided) because the cake does taste much like a breakfast food rather than decadent dessert.

I overcooked my sugar and water the first time and threw it out to start over. It's important to reach soft ball stage (235 degrees) because any hotter will make the sugar rock hard as it cools. You can test for soft ball stage by tapping a drip drop of it into a bowl of cold water. If you can pick it up and shape into a softened ball, its perfect!

I love love love the texture, but again, it was not sweet at all. I even used one stick less butter just because it came together so fast in my kicthenaid. And it actually did what its supposed to- curdle and separate but then gracefully come back together into a fluffy frosting (credit that to the patience of softball stage).

Blueberry Lemon Jam Notes:

I used frozen blueberries, and began to puree in the blender as instructed. That did not even work. So, I put them in the pan over medium heat, just like I make raspberry sauce. They begin to break down, mash out the juices from them, and strain. Return to heat and add other ingredients. I even added some cornstarch mixed with some cold water just to thicken it slightly so I didn't have to cook it for so long. I wouldn't call this jam, it was sauce. It may look like jam in my pictures, but it was liquidy sauce that just seeps into the cake. I would add 1/4 cup more sugar next time (counteract the breakfast food flavor).

Lemon Blueberry Marble Cake from Sky High

Blueberry Lemon Jam

• 3 cups blueberries, fresh or frozen
• ¾ cup sugar (I suggest 1 cup)
• 2 tbsp freshly squeezed lemon juice
• 1½ tsp grated lemon zest

Puree the blueberries with any juices that have exuded in a blender. Pass the puree through a coarse strainer to remove the skins. (I suggest to skip this altogether, and just strain the skins from pan in next step)

In a heavy medium saucepan, combine the blueberry puree with the sugar, lemon juice, zest and ginger (if using). Bring to a gentle boil over a medium heat, stirring often for 20 minutes, or until the preserves have thickened and are reduced to 1 cup.

To check the proper thickness place a small amount of a saucer and put in the freezer until cold. Drag your finger through it. If a clear path is made through the preserve then it is ready. Let the preserves cool before using. (Can be made up to 5 days in advance).

Lemon Blueberry Marble Cake

• 2 sticks (8 ounces) unsalted butter, at room temperature
• 2 cups sugar
• 2 tsp grated lemon zest
• 1½ tsp lemon extract
• 7 egg whites
• 3 cups cake flour
• 4 tsp baking powder
• ½ tsp salt
• 1¼ cups milk (or less, I used ¾ cup)

Preheat the oven to 350 degrees F. Butter the bottom and sides of three 8 inch round cake pans. Line the bottom of each pan with a round of parchment or waxed paper and butter the paper.

In a mixer, cream together the butter, sugar, lemon zest and lemon extract until light and fluffy. Gradually add the egg whites 2 or 3 at a time, beating well between additions and stopping occasionally to scrape down the sides of the bowl.

Combine the flour, baking powder and salt, whisk gently to blend. In 2 or 3 alternating additions, beat the dry ingredients and milk into the butter mixture, scraping down the sides of the bowl several times. Beat on medium-high speed for about 1 minute to smooth out any lumps and aerate the batter.

Scoop 1 cup of the batter into a small bowl. Divide the remaining batter equally among the 3 prepared pans, smoothing the tops with a spatula. This gives you a smooth surface to work with. Add 2½ tbsp (I used 8-10 tbsp) of the lemon blueberry jam to the reserved batter and blend well. Drizzle heaping teaspoons of this blueberry mixture over the batter in the pans. Use a skewer to swirl the blueberry mixture in short strokes to drag it down through the lemon batter without mixing it in.

Bake for about 25 minutes or until a cake tester or skewer stuck in the center comes out clean and the cake pulls away from the sides of the pan. Let the layers cool for 10 minutes before turning out onto a wire rack, peeling off the paper and leaving to cool completely.

Lemon Buttercream

• 1 cup sugar
• ¼ cup water
• 2 eggs
• 3 sticks (12 ounces) unsalted butter, at room temperature
• 2 tbsp freshly squeezed lemon juice
• 1 tbsp finely grated lemon zest

In a small saucepan, combine the sugar and water. Bring to the boil over a medium heat, stirring to dissolve the sugar. Continue to boil without stirring, occasionally washing down the sides of the pan with a wet pastry brush until the syrup reaches the soft-ball stage, 238 (I take it off the heat at 235) degrees F on a candy thermometer. Immediately remove from the heat.

In a large mixer bowl with an electric mixer on medium speed, beat the eggs briefly. Slowly add the hot syrup in a thin stream, pouring it down the sides of the bowl; be careful to avoid hitting the beaters or the syrup may splatter. When all the syrup has been added, raise the speed to medium-high and beat until the mixture is very fluffy and cooled to body temperature. This can take 15-20 minutes.

Reduce the mixer speed to medium-low and gradually add the softened butter 2 to 3 tablespoons at a time, beating well between additions. As you’re adding the last few tablespoons of butter, the frosting will appear to break, then suddenly come together like whipped butter.

Beat in the lemon juice and zest (if using), and the frosting is ready to use.