15 Unique Cake Fillings You Hadn't Thought Of

Cakes and cupcakes are among the most versatile desserts out there, but they have long histories, too. That can make it hard to see past a typical wedding cake or grocery-store birthday cakes. Yes, red velvet and chocolate are great, but you're here because you're looking for something completely different. These fun flavors will let you be as creative and adventurous with your cake fillings as you want.

Bourbon butterscotch

Let's jump right in with a great addition to any baking project: alcohol. (And it's not going to be the only alcohol we explore here, so if you're looking for something fun and unique to serve at an adult-only gathering, don't worry.)

Bakers Royale has an amazing recipe that combines a bourbon butterscotch filling with a banana cupcake and a toasted marshmallow frosting. If banana isn't your thing, this is a flavor that you can definitely try with something like chocolate or apple. The good thing about this one is that there are also a ton of good bourbon butterscotch sauce recipes out there, like this one from Epicurious. Make that to pour over the ice cream you're serving alongside the cake.

Marshmallow

The idea of toasted marshmallow frosting makes you think. Is there anything better than s'mores, and is there anything that says cool nights around blazing bonfires better than the taste of gooey marshmallows?

Nope. But can you put them inside a cake? Chocolate, maybe?

Yes, please! If that sounds like the most amazing thing ever, try this recipe from the Brown-Eyed Baker. You can't go wrong with layers of chocolate and marshmallow, all wrapped in a silky chocolate frosting. S'mores in cake form might be the perfect way to bring an autumn bonfire indoors, and you might even want to experiment with crumbly graham crackers to complete the reimagined dessert.

Parsnip

Have trouble getting the family to eat all their veggies? Putting them in cake form might help, especially when it's so well-hidden that there's no way you'd be able to guess the cake filling is made from parsnip.

The Unconventional Baker has a completely bizarre take on cheesecake that's guaranteed to be a hit if you're looking for something new, different, and — above all — tasty. This strawberry lime parsnip cheesecake features a nut- or seed-based crust (your choice) and a filler mixture that includes (of course) strawberries, limes, and cooked parsnips. Even if parsnips aren't your favorite vegetable, you'll have to admit that they add an amazing texture to this strange cake. Who knows? They might be such a hit that you decide to try them in more conventional ways, too.

Lavender

Even if you love the smell of lavender, you may not have ever considered making it a part of your culinary arsenal. It's light, it's airy, and it's one of those scents that brings up thoughts and feelings of fresh meadows in the springtime. Who doesn't need that every so often?

The Cake Blog pointed out how amazing a little bit of light, flowery influence can be and spotlighted it in their lemon and lavender buttermilk cake recipe. The cake is, of course, made from scratch and brushed with a lavender-infused simple syrup before the two layers of the cake are assembled with lavender frosting as the filling. The lemon comes from the lemon glaze drizzled over the top, finishing off a cake that's not too heavy, perfect for when you're craving a little bit of the spring season.

Rum

There's no sense denying it: rum is delicious. But the idea of rum-and-raisin anything seems sad. Isn't there a better way to incorporate all the flavors of rum into baking projects? Yes, there is.

Depending on what it is you're going for, a custard might be a great option for filling your desserts. This recipe for rum custard from Epicurus would work in cakes, cupcakes, and even donuts. If you're thinking about making something a little more rich and delectable, try this mocha layer cake with chocolate-rum cream filling. What's not to like about that sequence of words?

Peppermint

Every year, as we leave pumpkin-spiced-everything behind and as autumn marches onward to winter, we start to look for something more suited to cold winter days around the fire. Peppermint shows up in candy canes, but you can also use it to lift your wintertime cakes to the next level.

Sweetapolita has a brilliant recipe for a beautiful chocolate cake that's as tasty as it is elegant. If you're looking for something a little less intimidating (and who has tons of time during the holiday season?), Bon Appetit has a wonderfully chocolatey recipe for a triple-chocolate cake with chocolate peppermint filling.

Rose

Rose as a flavor has its roots in things like Turkish delight. It's harder to find in the U.S., which is a shame. Add rose to your baking projects and you'll find a flavor that's not overpowering but still brings a fresh, springtime feel to your dessert.

Boulder Locavore shares this recipe for vanilla cupcakes made with a sweet rose filling surprise in the center, while Epicurious gives us this suggestion on how to add some rose influence into the center of your cake and accent it with candied rose petals as a decoration. As much as you might like chocolate (and you're not wrong), this is one of those flavors that really comes to life against the subtle suggestion of a vanilla cake.

Cinnamon

Cinnamon is one of those flavors that isn't used nearly enough in baking. Of course, there are cinnamon rolls, which are so tasty that the idea usually sends you straight to the kitchen. Fortunately, Wilton's shows us that something doesn't have to be complicated in order to be tasty with this incredibly simple recipe for an irresistible cinnamon cake filling. There's no end to the possibilities with this one. I'd recommend trying it with apple cupcakes.

Caramel apple

Speaking of apples, who doesn't love a caramel apple? The combination of a tart apple and caramel is a win no matter what the season, so why wouldn't you put it in the center of a cake?

BBC Good Food shares this delicious recipe for toffee apple cake. While it may look complicated and intimidating, it doesn't have to be. (You can skip a couple of the decorative touches for the final product and still have a beautiful cake.) At the heart of the recipe is a cake that captures the essence of the caramel apple with a sticky caramel apple filling that you can't get enough of.

Avocado

Even if you like a bit of guacamole with your tacos, avocado can be one of those foods that just seems too distinct to use a lot of, especially in dessert. Your gut reaction might be denial, but it works. That's in no small part thanks to the texture of avocados, and it works perfectly to bring a unique flavor and a creamy texture to the table. Yes, even in cake.

BBC Good Food has a brilliant recipe for a chocolate cake that calls for avocado as a main ingredient in the frosting, which they also use as a filling between two layers. The recipe has another bonus, too. If you're looking for a moist, delicious cake recipe that doesn't include eggs, wheat, dairy, or nuts, this might be your new go-to recipe! (Yes, that's an exclamation point. If that applies to you, you know how exciting that is.) If you're feeling a bit adventurous (and if you love avocados), Crazy For Crust suggests another type of avocado filling made with heavy whipping cream, avocado, lime juice, and vanilla. This one keeps its avocado green color (while the previous recipe is a chocolate-based filling) and is screaming to be included in your Halloween cupcakes.

Wine

You knew we'd cover all your bases for adult-themed cakes and cupcakes, didn't you?

If there's anything that goes better together than wine and chocolate, it hasn't been discovered yet. That's just one of the reasons to love this recipe from Mountain View Vineyard for chocolate wine cupcakes with red wine frosting. The cake is made by righteously replacing the water with wine, and the cream cheese frosting is made with a dash of wine, too. In the center of the cupcakes is an incredible filling made with heavy whipping cream, chocolate chips, and more wine.

This recipe is tasty if followed, but there's plenty of room here for experimentation. Different types of wine will impact the flavor of the final product, so you have plenty of excuses to go back to this one again and again.

Chai

Chai is an incredibly unique flavor that most people are only familiar with in teas. It's a true comfort flavor, and there's not much better than curling up with a steaming mug of chai tea on a cold, rainy day.

If you like the flavor, Eat Cake for Dinner has a great recipe that will allow you to bring all those warm spices into your cakes. The chai spice mix is a bouquet of cardamom, cinnamon, cloves, ginger, and nutmeg, and it can be stirred into a buttercream base for filling or frosting. If you're looking for something that's even richer with spices, Indiaphile gives us her recipe for Ginger Cupcakes with Chai Cream Filling. The ginger is in the cake and the frosting while the chai is in the filling, making this the perfect cupcake for a cold winter evening.

Coffee

There's no shame in admitting it if you run on coffee. The stronger the better, right? And when you realize it can go in cake form? No words describe the happy.

This isn't your mom's coffee cake, either. That stuff was only called coffee cake because that's what you drank with it. This is cake made with the stuff of heavenly deliciousness. There are a couple recipes in particular you should try. Nigella Lawson came up with this espresso-fueled creation of walnut cakes layered together with a filling of coffee-flavored buttercream frosting. If that's not enough coffee, check out this recipe from Cookie Dough and Oven Mitt. The cupcakes, buttercream frosting, and ganache filling are all made with instant coffee, which has a flavor that can be tricky to manage in your morning cup o' joe but comes through amazingly well in cake form.

Green tea

While we're turning our favorite hot drinks into delightful desserts, what about green tea? It has a light, mild flavor and can easily be transformed into cake.

These two recipes are for green tea in cupcake form. Specifically, both feature green tea flavors in the buttercream frosting. If you aren't a fan of cupcakes, consider layering two (or three) cakes together with this unique green frosting in between. It might be just the thing you're looking for on St. Patrick's Day. Spoonful of Flavor uses green tea in the cupcakes and in the frosting, and it's all brought together with the taste of pistachios. A recipe from Ilona's Passion has the same double dose of green tea without the pistachios, instead using vanilla in the cupcakes itself. Either way, this is a gorgeous, light idea that's sure to surprise anyone who tries it.

Whiskey

Just for good measure, here's one more alcoholic filling that you can't go wrong with. This recipe is a brilliant shoutout to all the best types of Irish alcohol. The Blahnik Baker has what might be our favorite recipe here. Her chocolate Guinness cupcakes with whiskey caramel and Baileys buttercream hit the trifecta of all that's good in the world. The Guinness goes into the chocolate cake, while the Baileys Irish cream makes a buttercream frosting even better. And the filling? Whiskey and homemade salted caramel sauce. Her recipe calls for Jameson, but with so many types of whiskey out there it would be a shame not to experiment.