Description
A stunning triple-layer lemon blueberry cake featuring tender, moist cake layers loaded with fresh blueberries and bright lemon flavor, frosted with light and fluffy mascarpone cream frosting. Perfect for spring and summer celebrations!
Ingredients
For the Cake
- 2 cups (380 g) granulated sugar
- ½ cup (118 ml) vegetable oil
- 3 large eggs – room temperature works best
- 2 lemons – you’ll zest them both and juice them for about ¼ cup fresh lemon juice
- 1 teaspoon (5 ml) lemon extract – or vanilla extract if you prefer
- ½ cup (118 ml) light sour cream – or plain non-fat Greek yogurt
- 2½ cups (350 g) all-purpose flour
- 3 teaspoons (11.2 g) baking powder
- 1 teaspoon (5 g) salt
- 1 cup (236 ml) buttermilk – or regular milk in a pinch
- ¼ cup (59 ml) fresh lemon juice – from those 2 lemons
- 9 ounces fresh blueberries – washed and thoroughly dried
- 2 tablespoons (15.6 g) all-purpose flour – for tossing with blueberries
For the Frosting
- 16 ounces (450 g) cold mascarpone cheese
- 2¼ cups (532 ml) cold heavy whipping cream
- 1 cup (130 g) powdered sugar
- 1 teaspoon (5 ml) pure vanilla extract
- Optional: 1 jar (10 oz) lemon curd – for extra lemony goodness between layers
Instructions
Preheat your oven to 350°F (175°C). Now here’s an important step – prepare your three 8-inch round cake pans by lining the bottoms with parchment paper circles and greasing the sides really well. I like to use butter or cooking spray, then give them a light dusting of flour.
In your large bowl, beat together the sugar, vegetable oil, eggs, and lemon extract. Mix for about 2 minutes until the mixture is smooth and looks a bit lighter in color – you’ll see it become slightly fluffy.
Then add in your fresh lemon zest, lemon juice, and sour cream. Mix until everything is fully combined and smooth. This mixture might look a little separated at first, but keep mixing – it’ll come together beautifully!
In a separate bowl, whisk together your flour, baking powder, and salt. This step is important – it distributes the baking powder evenly so your cake rises uniformly.
Place your fresh, dry blueberries in a small bowl and toss them with 2 tablespoons of flour until they’re lightly coated. This flour coating is your insurance policy against sinking berries!
Gently fold the floured blueberries into your batter using a spatula. Use a folding motion (like you’re hugging the batter) rather than stirring. If you’d like, reserve a few pretty berries to press on top of the batter in each pan for that bakery-style look.
Divide the batter evenly between your three prepared pans – each pan should have about 1⅔ cups of batter. Use a kitchen scale if you want to be super precise!
Bake at 350°F for 20-23 minutes. Here’s my trick: rotate the pans halfway through baking (around the 11-minute mark). This helps them bake evenly, especially if your oven has hot spots.
Your cakes are done when a toothpick inserted in the center comes out clean or with just a few moist crumbs clinging to it. The tops should spring back when lightly touched, and the edges might just be pulling away from the sides of the pan.
Let the cakes cool in the pans for about 10 minutes, then carefully turn them out onto wire racks. Peel off the parchment paper and let them cool COMPLETELY before frosting. I cannot stress this enough – frosting warm cakes will result in a melted mess!
Pop your mixing bowl and whisk attachment in the freezer for 5-10 minutes. Cold equipment makes all the difference with whipped frostings! Keep your mascarpone and heavy cream refrigerated until you’re ready to use them.
Place the cold mascarpone in your chilled bowl and beat it on medium-low speed to soften it slightly. Slowly stream in the cold heavy cream while mixing – you’ll see the mascarpone loosen and become more liquid. This is exactly what you want!
Increase your mixer speed to high and beat until soft peaks start to form. Now add your powdered sugar and vanilla extract. Mix on low just until the sugar is incorporated (so you don’t create a sugar cloud in your kitchen!), then increase to high speed and beat until you have firm, stable peaks.
The frosting should be thick enough to hold its shape but still spreadable. If it looks too soft, pop the bowl in the fridge for 10 minutes and beat again.
Place your first cake layer on a cake board or serving plate. Spread about 1 cup of mascarpone frosting evenly over the top. If you’re using lemon curd (highly recommend!), spread a thin layer over the frosting, leaving about ½ inch from the edges.
Add your second cake layer and repeat – frosting, then optional lemon curd. Top with your final cake layer. Now frost the entire top and sides of the cake with the remaining frosting. I like to do a thin “crumb coat” first, chill for 15 minutes, then do the final frosting layer for that super smooth finish.
Decorate however your heart desires! I love topping mine with fresh blueberries, thin lemon slices, or a sprinkle of lemon zest for that pop of color.
Notes
Use fresh lemon juice only. Bottled lemon juice tastes flat and artificial. Fresh is where all the bright, zingy flavor lives!
Chill your frosting bowl and tools. This is non-negotiable for mascarpone frosting. Warm equipment will make your frosting too soft and potentially cause it to break.
Don’t overmix the batter. Once the flour is incorporated, STOP. Overmixing develops gluten and creates a dense, tough cake instead of that tender, fluffy texture we’re after.
Level your cakes if needed. If they dome slightly, use a serrated knife to level them before assembly. This creates perfectly flat, professional-looking layers.
Weigh your batter for even layers. Each pan should have the same amount for even baking. A kitchen scale makes this foolproof!
- Prep Time: 30 minutes
- Cook Time: 20-23 minutes
- Category: Dessert
- Method: Baking
- Cuisine: American