Lemon Filled Vanilla Cupcakes with Blueberry Swiss Meringue Buttercream Frosting

As promised: The Best Cupcakes Ever, Part II

(Click here for Part I, Chocolate Salted Caramel Cupcakes)


Yup, it's pretty much the ultimate cupcake.

It's a vanilla cupcake filled with gooey lemon curd and topped with blueberry Swiss Meringue Buttercream. It's like biting into a little piece of heaven.

Ok so...after finding the second love of my life (Hubby being the first), the Swiss Meringue Buttercream, I felt compelled to test it again to see if it was too good to be true. I mean, seeing as I tested out the first love of my life by dating him for seven years before walking down the aisle, logically, this buttercream deserves the same meticulous scrutiny. I don't just give away my love so freely, you know? =) Plus, publicly declaring something as being the ultimate is a pretty big statement to make. Since I'm putting my reputation as a cook and foodie on the line here, I had to be certain that it would withstand different recipe variations.

I saw on Crispy Waffle's site that she had a recipe for Strawberry Swiss Meringue Buttercream on a Grand Marnier cupcake. It served as inspiration for my blueberry lemon ones. On her site, she gives two recipe variations: one for the Swiss Meringue buttercream and one for the Italian Meringue buttercream. I simply substituted the strawberries in her SMB recipe for blueberries. She says that she prefers IMB, which is also something I've been meaning to try. But since this weekend was devoted to the SMB, I went with that recipe. Definitely stay tuned for when I try out the IMB. I plan on doing a full comparison of the two meringues, one of these days.

Step 1: The Lemon Curd Filling
(See below for recipe)

I love lemon curd. It's tangy and has a creamy, smooth, and silky texture. It's sooo delicious. It's slightly tart and sour, so it acts as a great way to balance out the sweetness of the cupcake and frosting. Although, it's entirely necessary. The cupcake and buttercream are subtly sweet and super delicious on its own. I just happen to love the flavor combination of blueberries and lemon, so I decided to go all out and make them lemon-filled. Please feel free to skip this step. The cupcake by itself with the fresh blueberry buttercream can definitely hold its own. The lemon filling just gives it an edge. =)

It's super easy to make. Start by whisking together the eggs, lemon juice, lemon zest, and sugar. (I couldn't find my whisk, so I went ghetto and used my hand-held mixer beaters. hehe)

Put it over med-low heat & whisk for about 8-10 min until it thickens.

When you take it off the heat, it'll be kinda lumpy from the zest and you might have some tiny pieces of cooked egg, so put it through a strainer. Seems like an unnecessary step, but trust me, you don't wanna skip it. You'll be surprised at all the left over chunks that end up in the sieve.

You'll get this silky & smooth mixture afterward.

It needs to chill in the fridge for 2 hours. Make sure to wrap it tightly, with the saran wrap touching the surface of the lemon curd. This way, it doesn't dry out. When it's well chilled and ready to go, stir until smooth again before using.

Step 2: The Vanilla Cupcake

I stick to this great vanilla cupcake recipe by WS. If you follow the directions meticulously, you should get a super moist and delicious cupcake. It's not too sweet and has a lovely, fragrant vanilla flavor. Make sure not to over mix, and please use real vanilla extract, not the imitation stuff. It really makes a difference.

Step 3: The Blueberry Sauce

The blueberry sauce for the buttercream is super easy to make. You basically puree them and that's it. Since I love blueberries, I doubled what the recipe called for and made it a "more coarse" puree, if that makes sense. I wanted it to still have chunks of blueberry here and there to give it that pretty "blue sprinkles" look. I chilled the blueberry puree in the fridge for about an hour. It will come out congealed, kinda like soft jello. I think this is what made it okay to double the blueberry puree. It didn't make the buttercream too soft to pipe. (See Crispy Waffle's site for recipe.)

Step 4: Fill the Cupcakes with Lemon Curd

I got this little injector/frosting bottle from Crate and Barrel a while back. It allows for a quick and easy way to fill your cupcakes. If you don't have one, simply use any frosting tip you have and a pastry bag. Insert the entire tip into your cupcake and squeeze until the curd starts over flowing, like so:

Smooth out the filling with your finger.


Step 5: The Swiss Meringue Buttercream

Please refer to my prior post: The Best Cupcakes Ever, Part I for details on how to make the frosting.


When the buttercream is smooth and finished, pour in your chilled blueberry puree and mix until well combined. Isn't it pretty with all the blueberry specks?

Step 6: Frost Your Cupcakes!



I usually don't post this many pictures of the finished product...

but they're so gorgeous that I couldn't resist!

They're the best when served right away. If you have to refrigerate them, make sure to let them rest at room temp for 20-30 minutes before serving. The frosting needs time to soften. Chilling it makes it lose its flavor temporarily until it softens again.

I can't even begin to describe how delicious they were! You'll just have to try out this recipe to see for yourself! There's a lot of steps to it, but it's totally worth it. Bring them to your next party and wow everyone with your awesome inner domestic goddess.

Hubby has the most spoiled palate ever now. And he's a big brat about it too! The other day, when we were in the baked goods section of Safeway, he wrinkled his nose at the cupcakes and remarked that he would never again eat one of those. lol. Later, when we were in the baking aisle and he saw me grab a box of cake mix, he told me in a very stern voice to "put it back," and once again conveyed to me that he would refuse to eat it. (For the record, I wasn't planning on feeding it to anyone, let alone him. I was going to use it as an experiment to practice my cake decorating skills.) When I set out to domesticate him after getting married, I didn't know I would create such a monster! lol. Anyway, consider yourself forewarned. If you make this for your husband/boyfriend, he might turn into a total diva and refuse to eat anything perceived to be sub-par!


Please click HERE for all the recipes shown in this entry.

Hazelnut Mascarpone Frosting

I experimented in the kitchen for about four hours to come up with this recipe. It was for Kevin's birthday, so I knew I wanted to do something special and unique.

I had this idea of creating a creamy hazelnut flavored mascarpone-base frosting. I had been thinking about the components of it for the past month but never got around to trying it. I knew it was going to be fantastic, so Kevin's birthday seemed like the perfect occasion to finally put my thoughts down on paper. (In the form of a recipe, no less!)

Mascarpone cheese has a rich and creamy taste, but not rich in the sense that it would be heavy on the palate. It's quite light and refreshing. It is similar cream cheese, but a lot higher in quality and has an incredibly silky smooth texture. Perfect for a summer treat!

Combine and mix well:
8 0z (1 container) Marscarpone Cheese - At room temperature
7 TBSP Butter - At room temperature
4 TBSP Heavy Cream
1 Cup Powdered Sugar
1/2 Cup Nutella

Refrigerate for at least 1 hour.

You get this beautiful & creamy hazelnut frosting. It's light, smooth, and silky! This frosting is perfect for the summer time when you're looking for something rich in flavor but not heavy on the palate.



So the frosting went fantastically well! The next part was figuring out what kind of cupcake to put it on. I knew I wanted to do something with chocolate, because chocolate and hazelnut are like PB&J- simply a great & classic flavor combination! But I didn't want an entirely chocolate cupcake because sometimes they can be heavy and overpowering. Since the delicate flavor of the frosting was supposed to be the highlight, I didn't want it to be masked by a heavy chocolate taste. Then, a light bulb went off in my head: I'll do a chocolate and vanilla swirl! I found a couple of great chocolate & vanilla cupcake recipes and went for it!


The recipe called for a semi sweet chocolate, but I used unsweetened chocolate, instead. This gave the cake a dark chocolate taste, cutting out some of the sweetness. Perfect!




Melt butter with the chocolate...





...to create a gorgeous bowl of dark chocolate syrup! Add your dry ingredients and set aside your chocolate cake batter to start on the vanilla.


The vanilla batter was smooth, fluffy, and white. It looked beautiful next to the chocolate one! Spoon in the batter, alternating between chocolate and vanilla. When finished, take a fork and run it through the cups to get swirls.



They were pretty, even without the frosting!




I put the chilled frosting into a pastry bag and pipped it on. I made a batch of mini ones because Kevin, being the diva that he was, demanded them. =) They were super cute!



The frosting was a hit! A lot of people at the party were amazed by the surprisingly unique flavor and asked about the recipe... at which point I shamelessly promoted my blog. hehe.


Next time, when I use this frosting, I will be sure to make only mini cupcakes. The highlight of this cupcake was its frosting, so with the mini ones, you can do a half cake and half frosting ratio. When eating the big ones, I felt like there was too much cake and not enough frosting! =)