Mini Vanilla Cake with Brown Butter Frosting

This mini vanilla cake recipe features two light and tender 6-inch mini cakes sandwiched together with creamy brown butter frosting.

A mini cake like this serves eight generous slices making it the perfect size cake for a small group. It's a fluffy and light vanilla cake base, paired with a light and creamy brown butter swiss meringue buttercream.

The frosting really elevates the simple cake, with notes of caramel and toffee.

Jump to:

• The mini vanilla cake layers
• The Brown Butter Frosting
• The ingredients
• Method
• The Swiss Meringue Buttercream
• Frosting the cake
• Serving and storing
• Full Recipe

The mini vanilla cake layers

The cake is made up of two small cakes. They are baked in two round 6-inch cake pans. If you just have one cake pan, you can bake one layer at a time and use the same pan twice.

Or, make these small-batch vanilla cupcakes!

The cake is a basic vanilla cake that uses both oil and butter to create a moist cake full of flavor. You'll need an electric hand mixer or a stand mixer to cream the butter, oil, and sugar together. This is a key part of the cake texture.

The Brown Butter Frosting

This frosting is the star of the show. It's a Swiss meringue buttercream with added brown butter. This makes it rich in flavor, creamy, yet light. Brown butter is amazing in baked goods, it brings so much flavor by just doing something so simple.

Brown butter is butter that has melted and then cooked a step further so that the milk solids in the butter caramelize. This gives a wonderful caramel flavor to the butter.

It's delicious in brown butter oatmeal raisin cookies, brown butter ice cream, brown butter banana bread and of course, this Swiss meringue buttercream.

Swiss meringue buttercream

Swiss meringue buttercream (SMBC) is made by gently cooking egg whites and sugar in a double boiler until the sugar has melted. The mixture is then whipped into a stiff meringue. Next, lots of room temperature butter is whisked into the meringue, a little at a time, until the mixture comes together into a cloud of delicious frosting. 

Lastly melted and cooled white chocolate is beaten in until the frosting is thick and silky.

Swiss buttercream can seem like a tricky frosting to make as some things can go a little wrong. The good thing is, that there is usually an easy fix for all of the issues! Read this chocolate Swiss meringue buttercream guide for more details.

The ingredients

For this small vanilla cake recipe and the frosting, you only need simple ingredients. Note - The amounts are given in the printable recipe card below but here is an ingredients list.

• All-purpose flour.
• Baking powder
• Baking soda
• Salt
• Unsalted butter
• Vegetable oil (you can use liquid coconut oil or other mild-tasting vegetable oil)
• Granulated white sugar
• Large eggs
• Vanilla paste or pure vanilla extract. (Don't skimp on the quality of this as it's a key part of a good vanilla cake.)
• Whole milk
• Vinegar or lemon juice. A little acidity helps the cake rise and creates a more tender crumb as acid halts the gluten development in the flour.

For the frosting

• Egg whites
• Granulated sugar
• Unsalted butter - Some will be browned and some will be left as is
• Vanilla paste or extract
• Salt

Equipment

You'll need a hand mixer or stand mixer to cream the butter and sugar in the cake.

For the frosting, a stand mixer is needed because the egg whites and butter need a long period of mixing.

Method

The 6-inch cake layers

Preheat the oven to 350°F/180°C. Grease two 6-inch cake pans and line the bottom of the pans with parchment paper.

In a small bowl, whisk together the flour, baking powder, baking soda, and salt, and set this flour mixture aside.

In a bowl of a stand mixer fitted with a paddle attachment or in a medium bowl and electric mixer, beat together room temperature butter and oil on medium speed until it's creamy and combined. Add in the granulated sugar and beat on high speed for around 3-4 minutes until it's very light in color and creamy and increased in volume.

Add in the vanilla and eggs, one at a time, and beat in after each addition.

In a small bowl, stir together the milk and vinegar.

Add half the dry ingredients to the butter mixture along with half the milk. Use a rubber spatula to stir it in well until well combined. Repeat with the rest of the dry ingredients and milk mixture.

Divide the cake batter evenly amongst the cake pans and smooth down the tops of the batter with a small offset spatula.

Bake the cakes for around 25 minutes until the tops spring back when touched and a skewer inserted into the middle of the cakes comes out clean.

Remove the cakes from the oven and let them cool for 10 minutes in their pans, then turn them onto a wire cooling rack and allow them to cool completely.

The Swiss Meringue Buttercream

Brown butter

While the cakes are baking, brown the butter so it has a chance to cool.
Over medium heat, let the butter meltdown. Avoid using a dark pan as you will struggle to see the caramelization of the butter and run the risk of burning it.

Once you have melted butter, let it cook further for around 3 minutes, stirring occasionally until the milk solids in the butter have caramelized into a golden amber color and the butter smells nutty.

Pour the browned butter into a flat dish and refrigerate it until it has just solidified, but is not too cold or rock hard.

EGGWHITES

Step 1 - Bring a pot of water (with 1 inch of water) to a simmer. 

Step 2 - In the bowl of a stand mixer, add egg whites and granulated sugar. Balance the bowl over this simmering water bath. Whisk continuously as the egg whites warm-up and keep whisking until all the sugar has dissolved or the temperature reads 160°F (71°C) on an instant-thermometer. Don’t stop stirring or some egg whites may overcook on the edges of the bowl. 

Step 3 - Once the sugar has dissolved, place the bowl in your stand mixer fitted with the whisk attachment. Beat on medium-high speed until a meringue with stiff peaks forms and the meringue has cooled down to room temperature. When you touch the sides of the bowl they shouldn't feel warm. 

Step 4 - With the mixer on medium-high speed, feed in the solidified brown butter, followed by the rest of the butter, a cube at a time. Allow the butter to incorporate fully before adding the next cube. At this point, the frosting can suddenly appear split or curdled and look like cottage cheese. Just keep beating the mixture until it comes together into a thick and cohesive buttercream. This can take a lot of beating so don't give up if it doesn't seem to come together - it will. Keep beating it until it no longer looks greasy.

Step 5 - Once the mixture is thick and cohesive, beat in the vanilla and salt and beat until thick and fluffy. Switch to the paddle attachment and beat on low-medium speed for another minute or two to remove some of the larger air bubbles in the buttercream.

Frosting the cake

Only frost the cake once the layers are completely cooled. You can speed up the cooling process by placing the cakes in the fridge or freezer.

Use a serrated knife to level the cooled cakes and make their tops flat and even.

Place one layer of cake on a cake turntable or cake stand. Scoop on some frosting and use a small offset spatula to spread out the frosting on top of the cake layer. Add on the second cake layer. If you place the top layer upside down it will give a nice smooth top to work with.

Add a few scoops of frosting on top and spread it out with the spatula, and add a thin coat of frosting around the cake. Use a bench scraper to smooth it out, then chill the cake for around 20 minutes in the fridge until the frosting has firmed up.

Add a thick layer of frosting to the entire cake and use a bench scraper to smooth it out. Then you can use a serrated bench scraper to make patterns on the side of the cake if you wish.

The remaining frosting can be added to a piping bag and piped on top of the cake or used to pipe decorations of your choice.

Serving and storing

Refrigerate the cake until ready to serve, then take it out of the fridge at least 30 minutes before slicing.

Leftover cake can be stored in the refrigerator in an airtight container for up to 4 days.

Make ahead

The cake layers can be made ahead of time and frozen until you need them. Frozen layers of cake are also easier to frost.

The frosting can also be made ahead of time and refrigerated for up to 3 days or frozen for up to 3 months. Read more about how to bring it back to a fluffy texture in this Swiss meringue buttercream post.