Wondering how to frost a cake and get those perfectly even layers, smooth sides, and squared edges? Well, my friends you have come to the right place. Here you will find a detailed breakdown of all the things from a pastry chef’s perspective to ensure success.
Before moving forward, keep in mind your fridge and freezer are your best friend—you can forget about putting silly bits of parchment or wax paper under your cake, literally no professional baker or pastry chef ever does that because it’s a waste of time, material, and there’s this thing called a wet paper towel you can use to clean your cake board or platter if needed. So, let’s get started!
Before we dive into the how, let's talk about the what. As in, what you need! While you don't necessarily need the fancy tools that pastry chefs use, there are some essentials.
- 2 to 4 cake round layers, frozen
- 1 to 2 quarts of your favorite buttercream or frosting at room temperature and freshly paddled in a table top mixer so it’s smooth and silky without air bubbles.
- For 6-inch to 8-inch cakes you will need 1 quart or more depending on the number of layers and how much decorating you intend to do. For a 9-inch layer cake we suggest at least 1 1/2 quarts of buttercream.
- Serrated knife
- A small and large offset spatula, plus a regular rubber spatula
- Plastic or silicone straight-edge pastry scraper or cake smoother. We recommend a scraper at least 6-inches wide, especially for taller cakes
- Cake board, plate, or platter you intend to serve the cake on
- Cake turntable with a rubber mat or wet paper towel folded flat and placed between the turntable and cake board so it doesn’t slip
- Refrigerator space to fit the entire cake
- Disposable or reusable pastry bag and piping tips, both optional
Whether you call it frosting or buttercream, you'll want to have your favorite recipe prepared before assembling the cake layers. Just like we set up mise en place when cooking, it's helpful to have all components and tools ready as you need them. Based on the size and number of layers, you can reference our checklist above to understand how much buttercream to prepare. If made ahead of time, make sure the buttercream is at room temperature before assembling.
Below, you'll find our favorite recipes along with tips for flavor variations:
- Buttercream Frosting
- Italian Buttercream
- Swiss Meringue Buttercream
- Vegan Buttercream Frosting
- Cream Cheese Frosting
- Brown Sugar Frosting
- Chocolate Buttercream Frosting
Prepare the Cake
You baked off your cake, prepared the frosting, and now you're ready to make the magic happen. But before we get into layering and decorating, we need to talk cake. The key to getting clean and even layers is working with frozen cake layers. I wrap each individual layer of cake and freeze them flat. This is because cakes, along with mostly anything in the pastry world, will cut much cleaner when cold or frozen. Plus, it will be much easier to assemble and frost.
So go ahead and grab that cake turntable. Unwrap one layer of cake, keeping the plastic wrap in between the bottom of the cake and top of the turntable. Most cakes will dome a little on the top when baking, so to create perfectly even layers we need to trim that dome off.
Now, drop down to eye level with the cake. Using a serrated knife start cutting into the cake where the top of the cake ends and the dome starts. Slice into the cake only a couple inches then turn the turntable and continue to cut into and around the perimeter of the cake, using the top edge of the layer as a guide. Once you’ve gone all the way around you can finish by sawing completely through the layer. Repeat with the remaining layers and set aside.
- If your layers are thick, you can halve them using this same technique.
- Don't toss those cake scraps! Save your scraps for munching or turning into cake pops. The scraps can also be wrapped in plastic and frozen for up to 6 months.
Assemble the Cake
Place a non-slip mat or wet paper towel folded flat and placed between the turntable and cake board or plate so it doesn’t slip. Place a layer of cake, bottom side-down, onto your cake board. Use the rubber spatula to scoop enough buttercream to create 1/4-inch to 1/2-inch layer of filling between the cake layers.
Spread the buttercream all the way to the edge of the cake using the tip of a small offset spatula. Hold the elbow of the offset spatula in the center of the cake at a 45-degree angle and gently spin the turntable towards you while smoothing out the layer of buttercream. You can scrape off any excess back into the bowl of buttercream.
Top with the second layer, trimmed side-down, and repeat these steps until you use all the cake layers, making sure to finish with the bottom-side up and trimmed side-down of the top cake layer.
Adding a Filling
If you are using a different filling like pastry cream, curd, jam, fruit, or more, you will need to create a border around the cake so the filling doesn’t seep out.
- To do this set up a pastry bag with either a 1/2-inch circle tip or simply cut a 1/2-inch hole in the tip of the bag.
- Spread a 1/4-inch layer of buttercream onto the cake layer as instructed.
- Place some buttercream inside the prepared bag and pipe a circle around the top of the smoothed buttercream layer.
- Fill the inner part of the circle with the filling, then place the next cake layer on top. Continue until you've placed the last cake layer on top.
- Not all layers are created equal. Sometimes they get banged up or dented in the freezer or while unmolding, so I always put my ugliest layer in the middle and the bottom, and my prettiest one on top.
- It is very important the buttercream or frosting is at room temperature. It is very important the buttercream or frosting is at room temperature. Too cold and it won’t spread nicely, too warm and it will be hard to build a thick layer.
- If you would like to impart additional flavor to the cake or increase moisture, you can brush the layers with a simple syrup before layering with frosting or filling.
- As you stack your layers, make sure you get eye-level with the cake and use the turntable to see all angles of the cake. Make sure all the layers are evenly stacked straight. You can gently use your hands to nudge any out-of-place layers in one line.
Crumb Coat the Cake
Now that you have your cake assembled, it’s time to do the crumb coat. This technique builds a thin base layer of frosting on the cake to lock in any crumbs, making your final layer of buttercream more smooth and clean.
Place about a cup of buttercream on the top of the cake, then spread it evenly towards the edge of the cake using the tip of a large offset spatula. Smooth it out by placing the elbow of the offset in the center of the cake holding it at a 45-degree angle with the blade parallel to the base, then gently spin the turntable towards you until you’ve gone around a couple of times and you are happy with how smooth it is.
As you smooth out the top, buttercream will overhang on the sides. We want this! Use the tip of your offset to push the buttercream down the sides of the cake, while holding the offset vertically. Spin the turntable towards you to smooth out the sides of the cake.
Use the back of offset to add more buttercream to any gaps you may see between the layers. Hold the offset vertically, perpendicular to the base, with the edge touching the left side of the cake at a 45-degree angle (if you are left-handed hold it on the right side of the cake) and spin the turntable towards you a couple rotations to smooth.
Chill the entire cake in the fridge for about 10 minutes to help set up your base coat so you can create a clean finished product.
Frost the Cake
Before you apply the final coat of buttercream, you need a game plan for how you envision your finished cake. Do you want straight, completely smooth edges? Maybe piped with some buttercream swirls or pearls? Do you want a more rustic look? With that in mind, you will know how to approach the final coat of frosting. Whether that's keeping a meticulous eye on imperfections or embracing the whimsical swooshes of frosting.
With the crumb coat set, we can apply the final coat of frosting. Place a large dollop of buttercream on top of the cake and use the large offset spatula to smooth into an even layer like before.
Add a little buttercream at a time around the sides of the cake, then use wide pastry scraper to evenly coat the cake. Our goal is to first apply an even coat of the buttercream around the cake, then we can focus on smooth sides.
If you want a more rustic abstract look, use a small offset or the back of a spoon to add swoops of buttercream to the sides and top.
To get straight, smooth sides, get eye-level with the cake and fill in any gaps or uneven areas of buttercream. Smooth the sides of the cake by holding the wide pastry scraper near the back of the cake at a 45-degree angle and pull the turntable towards you. Scrape off any excess buttercream back into the bowl. Smooth out the cake a few rotations until it is to your liking, applying more buttercream as needed. Place the entire cake into the fridge for 10 minutes to set the frosting.
- To fill in the smaller gaps of buttercream it may be easier to use your small offset spatula in areas, as needed.
- For even smoother edges, pop the frosted cake in the freezer for 10 minutes to really set the buttercream. Run the small offset spatula under hot water or use a kitchen torch to heat the back side, then smooth out any imperfections. You can use this technique to help with making a cleaner, flat top as well.
Decorating & Garnishes
You're almost there and now it's time for the fun. You can serve the frosted cake as is or go a step further by piping on a border, adding a ganache drop, or topping with sprinkles. The choice is yours. Envision the cake of your dreams and attack!
An easy way to make a cake look finished is to pipe small pearls, stars, or waves around the base of the cake. You can do this by setting up a piping bag with a 1/4-inch tip (or size of your choice), then pipe around the circumference. If you like, you can repeat this same look around the circumference of the top of the cake.
The best way to get the most symmetrical look when piping borders is to work in sections of the cake and think of it like a clock. For example, pipe the first swirl at 12 o’clock, the next at 6 o’clock, then 9 o’clock, then 3 o’clock. From there you can pipe in the middle of each swirl and repeat until you are happy with the look.
Our Favorite Garnishes
Go beyond the buttercream and garnish your cake with some of our favorite treats, including:
- Berries or other fresh fruit
- Chocolate curls or flakes
- Toasted coconut
- Edible or regular flowers
- Ganache or caramel drip (note, you should add your drip around the top of the cake, then pipe any additional buttercream accents over top)
- You can completely coat the sides in sprinkles, almond slivers, or toasted coconut by gently pressing handfuls onto the applied buttercream.
You can keep your cake in a stand with a lid or airtight container for about 3 days at room temperature, a week in the fridge, and 6 months in the freezer. Of course, all of this depends on what exact ingredients are used in your cake.