Let's be real: cakes are just as much about looks as they are taste. So knowing how to crumb coat and frost a cake is definitely a skill worth mastering. Here's what you need to know to make yours look like a pro did it.
What You Need
- Piping bag (optional)
- Large round piping tip (optional)
- Offset icing spatula
- Bench scraper or straight icing spatula
How to Crumb Coat a Cake
Before learning how to frost a cake, you first need to know about crumb coating. This is when you add a thin layer of frosting to the exterior before adding a thicker, final coat of frosting. The thin layer of frosting traps stray cake crumbs and prevents them from popping up in your finished cake. Adding a crumb coat also helps fill in any gaps between your cake layers to create a solid surface before adding a smooth, final coat.
To crumb coat your cake, put some of your buttercream into a separate, smaller bowl — that way you won't risk introducing crumbs into the frosting you'll use for the final, perfect coat. Use an offset spatula to add a bit of buttercream to the cake, then smooth it out with your bench scraper.
If it's warm where you are, chill your filled cake until firm before adding the crumb coat so the layers don't wobble while you're working.
Repeat until all the gaps on your cake are filled. Don't fret if the crumb coat isn't entirely smooth, but catch the holes — a gap-free surface is the key to a flawless final coat.
Once your cake is crumb coated, place in the fridge to set for 15-20 minutes, or until firm to the touch. If you're working with American buttercream , the cake can be left at room temperature until the buttercream has formed a crust (about 20 minutes).
How to Frost a Rustic-Style Cake
Once the crumb coat is set, you're ready to actually frost your cake. A loose, rustic look is an easy aesthetic to pull off.
1. Plop the Frosting on the Cake
Scoop a mound of frosting on top of the cake. (Aim for a little over 1 cup for a 6" round cake, or about 2 cups for an 8" round cake.) This may feel like a lot of frosting, but it's correct.
Use an offset spatula to spread the frosting out while rotating the turntable, pushing the frosting over the top edge to make an overhang. Move the spatula through the frosting to create fluffy peaks and valleys.
2. Spread the Frosting Down the Sides
Use the offset spatula to spread a thick layer of additional buttercream onto the sides of the cake while continuously rotating the turntable. Pull the excess frosting from the top edges down onto the sides as well. Create fluffy peaks and valleys all over the sides of the cake, just as you did with the top.
3. Clean Up the Top Edge
Knock down any buttercream that's poking up and spread as needed to make the edge fairly even all around. Avoid overworking things here — once you have a nice rustic look, you're done!
How to Frost a Smooth Cake
This is what you should do when you want a more smooth, professional finish.
1. Spread Frosting on Top of the Cake
Scoop (or pipe) a mound of frosting on top of the cake. Be generous, as a nice thick layer is easier to make smooth.
Use an offset spatula to spread the frosting out, pushing it over the the top edge.
2. Smooth It Out
Once the top of the cake's covered, hold the blade of the spatula against the top of the cake. Keep the spatula steady while you use your other hand to spin the turntable. Spread and spin until the top of your cake is level and smooth. (Again be careful not to overwork it.)
3. Spread Frosting on the Sides
Load your spatula with frosting and apply it thickly to the side of your cake. (You can also pipe it on with a pastry bag and a large round tip if you prefer.) Smooth it out by holding the long edge of a bench scraper, or a straight icing spatula, vertically and using your other hand to spin the turntable.
Stop every few spins to scrape excess buttercream back into the bowl. Dip the spatula in warm water and wipe it down with a paper towel if frosting starts to build up. Slightly warming the spatula like this helps the buttercream get even smoother.
4. Make It Perfect
Fill in holes if needed and re-smooth by giving the turntable another spin.
Repeat spinning and scraping until the sides are as smooth as you'd like them to be.
5. Clean Up the Top Edge
After the sides of the cake are smoothed, you'll see some excess buttercream peeking up over the top edge. Working as precisely as you can, use the flat edge of an offset spatula to swipe the excess buttercream in toward the center, creating a crisp edge while maintaining a smooth top.
There you have it — a beautifully smooth cake!
Photos by Erin Bakes
Learn More Now
Learn how to flavor buttercream and decorate more cakes and cupcakes in our free guide, Not-So-Basic Buttercream Decorating Ideas.