These Lemon Blackberry Cupcakes are homemade lemon cupcakes topped with a fresh blackberry Swiss meringue buttercream. They’s bursting with flavor!
![a plate of frosted lemon cupcakes topped with berries with a cake stand full of cupcakes in the background](https://beyondfrosting.com/wp-content/uploads/2022/06/Lemon-Blackberry-Cupcakes-010.jpg)
Lemon Cupcakes with Blackberry Swiss Meringue Buttercream
Whenever berries go on sale, I stock my fridge full, because how could I not?! And that usually means I end up trying to use the berries up with last-minute recipe ideas…like these Lemon Blackberry Cupcakes!
The lemon cupcakes are made with lemon juice, lemon zest, and lemon extract for all the citrusy flavor and they’re perfectly moist thanks to the addition of sour cream. The cupcake itself is a little more dense, similar to a sponge cake, which contrasts beautifully next to the light, silky, and buttery blackberry Swiss meringue buttercream.
Key Ingredients
- Lemons – we’ll use both the fresh lemon juice and lemon zest for our lemon cupcakes. The lemon zest goes in the frosting too!
- Lemon Extract – if you can’t find lemon extract, vanilla extract will work as well.
- Sour Cream – sour cream is the key to super moist cupcakes.
- Buttermilk – buttermilk adds moisture and brings out the lemon flavor with some extra acidity. If you don’t have buttermilk, regular will work as well. You can also easily make your own buttermilk using regular milk and lemon juice or white vinegar!
- Butter – use unsalted butter so you don’t end up with salty cupcakes.
- Egg Whites – egg whites whipped with granulated sugar are the base for our meringue frosting. And no, whole eggs will not work!
- Blackberries – you’ll make fresh blackberry puree by just blending them up in a food processor. You can leave it as-is or strain the puree for a smoother frosting.
How to Make Lemon Blackberry Cupcakes
For the Cupcakes
- Combine the wet ingredients: In a bowl, combine sugar, oil, eggs, and lemon extract. Beat until well incorporated, then stir in lemon zest and sour cream. In a separate bowl, mix together the remaining dry ingredients. Combine the lemon juice and buttermilk.
- Add the dry ingredients: To the flour mixture, add half of the dry ingredients, and half the buttermilk mixture. Mix until just incorporated, then add the rest of the dry ingredients and buttermilk.
- Divide and bake: Use a large cookie scoop to portion the batter out into a lined cupcake tin. Fill each liner 2/3 full. Bake at 350ºF for 14-16 minutes, then cool completely.
For the Frosting
The frosting is my Swiss Meringue Buttercream with added blackberry puree and lemon zest! Be sure that the butter is at room temperature. Here’s how to make it:
- Puree the blackberries: Use a food processor to puree the blackberries. Strain to remove the seeds if desired.
- Combine the sugar and egg whites: Set a bowl over a pot with water on the stove. Heat the water to medium-low, then add sugar and egg whites. Stir constantly until the mixture reaches 140ºF.
- Beat into a meringue: Place the mixing bowl onto your stand mixer and use the wire whisk attachment to beat the mixture until whipped and a meringue starts to form, increasing the speed every few minutes.
- Add the butter, blackberries, and lemon: Turn the mixer to medium-low, then add the butter, 1 tablespoon at a time, until fully combined. Switch to the paddle attachment and continue beating until smooth, then fold in the blackberry puree and lemon zest.
- Decorate the cupcakes: Transfer the frosting to a large piping bag with a large open round tip and pipe onto the cooled cupcakes.
Tips for Working with Swiss Meringue Buttercream
- Clean utensils: Even the slightest bit of grease can throw off a meringue-based frosting. Use a paper towel and vinegar to clean the bowl, whisk and spatulas prior to making the frosting.
- Use a candy thermometer. Be sure you have a candy thermometer at the ready so that you can take the sugar/egg white mixture off of the stove as soon as it reaches 140ºF.
- If you don’t have blackberries available, raspberries or strawberries would make a great alternative as well.
Can You Freeze Lemon Cupcakes?
If you want to freeze the cupcakes, you’ll need to do so before they’re frosted. Bake and cool as directed, then store in the freezer. When you’re ready to prepare, thaw to room temp, make the frosting, and frost as instructed.
How to Store Finished Lemon Cupcakes
Fully frosted lemon blackberry cupcakes will last in an airtight container on the counter for 2 days. Swiss Meringue frosting is heavily butter-based, and does not hold up well in high temperature or humid environments. If refrigerated, then the frosting will harden. It should be served at room temperature.
Lemon Blackberry Cupcakes
- Prep Time: 30 minutes
- Cook Time: 15 minutes
- Total Time: 45 minutes
- Yield: 24 cupcakes
- Category: Cupcakes
- Method: Oven
- Cuisine: American
Description
These Lemon Blackberry Cupcakes are homemade lemon cupcakes topped with a fresh blackberry Swiss meringue buttercream. They’s bursting with flavor!
Ingredients
For the Cupcakes:
- 2 cups granulated sugar
- ½ cup vegetable oil
- 3 large eggs
- 2 lemons- zested and juice
- 1 teaspoon Lemon (or vanilla) extract
- ½ cup light sour cream
- 2 ½ cups all-purpose flour
- 3 teaspoons baking powder
- 1 teaspoon salt
- 1 cup buttermilk (or milk)
For the Frosting:
- 2 cups unsalted butter, at room temperature
- 5 large eggs whites
- 1 cup granulated sugar
- 6 ounces blackberries, pureed
- Zest 1 lemon
Instructions
For the Cupcakes:
- Preheat the oven to 350°F. Line a cupcake pan with cupcake liners.
- In a large mixing bowl, combine the sugar, vegetable oil, eggs and lemon extract. Beat on medium speed until the eggs and oil are well incorporated. Scrape down the bowl as needed.
- Next, zest 2 lemons and then juice the lemons. Set the lemon juice aside and add the zest and sour cream to the batter, beating until well combined.
- Combine the remaining dry ingredients in another bowl. Add half of the dry ingredients, the lemon juice, and half of the buttermilk and mix just until the flour starts to incorporate. Then add the remaining dry ingredients and buttermilk. Beat until all of the ingredients are well combined. Use a spatula to scrape down the sides of the bowl and stir the batter from the bottom to the top to ensure it’s well mixed.
- Using a large cookie scoop, divide the batter evenly, filling each liner 2/3 full. Careful not to overfill. Bake at 350°F for 14-16 minutes. Test the cupcakes for doneness by inserting a toothpick into the center of the cupcake. If the toothpick comes out clean, the cupcakes are done. Cool Completely.
For the Frosting:
- Puree the blackberries using a food processor. Optional, strain the blackberry puree through a fine sieve to make a smoother frosting. Set aside.
- Set your bowl over top of a pot with water, just enough to cover the bottom of the pot. You do not want the water to boil and touch the bottom of your mixing bowl. Heat the water on medium to medium-low heat.
- Combine the sugar and egg whites in your mixing bowl and stir (using your greaseproof spatula) constantly until the mixture reaches 140° F. This is the most important part; you do not want to egg whites to cook. When it reaches 140° F, the sugar should be dissolved in the egg whites. You can test this by placing a drop on your fingertips and rubbing them together. The mixture should be completely smooth.
- Place the mixing bowl on your stand mixer. Using the wire whisk attachment, beat the egg whites. Start on low and increase the speed to medium after 2 minutes.
- Beat for another 3 minutes on medium. At this point, your frosting should have turned white as the egg whites are whipped and the body of the meringue starts to form.
- After 5 minutes, increase the speed to high. You will notice that as you increase the speed, the body of your meringue will also increase. It will start to look glossy as the peaks begin to form. Beat for another 5 minutes.
- After you have beat the meringue for a total of about 10 minutes, the bottom of your mixing bowl should be cooled completely. Your SMB should look kind of like whipped cream. Scrape down all sides and bottom of the bowl.
- Turn your mixer down to medium-low. Slowly add your butter, about 1 tablespoon at a time, ensuring it is mixed well after each addition. Once you have added all your butter. Mix for another minute and scrape down the sides of the bowl.
- Switch to the paddle attachment and continue beating on medium to allow all the air bubbles to escape. In about 2-3 minutes the frosting is smooth.
- Lastly, fold in the blackberry puree and lemon zest and stir well to combine. Use a large piping bag fitted with a large open round tip to pipe the cooled cupcakes.
Notes
- It’s helpful if you have an candy thermometer to make this frosting
- For more helpful hints on making Swiss Meringue Buttercream, visit my how-to post.
Nutrition
- Serving Size:
- Calories: 353
- Sugar: 26.4 g
- Sodium: 135.9 mg
- Fat: 21.6 g
- Carbohydrates: 38.5 g
- Fiber: 0.8 g
- Protein: 3.7 g
- Cholesterol: 66.7 mg
The cupcakes are amazing!!!!! The lemon flavor is great. I feel like the frosting has a little too much butter for my liking. I halved the butter the second time and it was a much stronger flavor.
Thank you for sharing Ashley! Were you able to have enough frosting for all your cupcakes when you halved the butter?
The flavors in the cupcake and frosting pair so well and are sooo good. Be prepared for the frosting to take a while (this was much first time making frosting) but it is so worth it!
Awesome Marissa!! Thank you for sharing! Yes Swiss Meringue buttercream does take quite a bit longer but I believe the payoff is worth it.