The whole point of covering a cake in fondant is to give it a perfectly smooth surface to decorate. But if you lay that fondant right over a bare cake, you'll get lumps, bumps, and color showing through. This video demonstrates how to cover your cake with a layer of buttercream called a crumb coat that acts as a base layer for a fondant coating.
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|Episode 1: Leveling and Splitting Layer Cakes
||Episode 2: Crumb Coat for Fondant Cakes||Episode 3: Buttercream Effects|
|Episode 4: Fondant-Coated Cake||Episode 5: Doweling and Stacking Multi-Tiered Cakes||Episode 6: Fruit Leather Decorations|
|Episode 7: Simple Fondant Shapes||Episode 8: Stamping||Back to Series Intro|
If you're used to finishing cakes with buttercream only, when you hear the term crumb coat, you're probably picturing a very thin coat of frosting under a thicker outer layer of buttercream. (See a video of how to do that style of crumb coat.) But in the world of fondant cakes, the crumb coat is actually a rather thick layer of buttercream UNDER your fondant, which not only traps and seals in the crumbs but also prevents, say, a chocolate cake from showing through a white fondant.
Your buttercream should be fluffy and not at all stiff-if you've made it ahead and refrigerated it, bring it back to a fluffy consistency by whipping it in the stand mixer.
You CAN scoop some buttercream straight from the bowl onto your cake and spread it around, but it actually goes on more evenly if you pipe it. Fit your pastry bag with a very large basket weave tip, and simply pipe large horizontal strips all the way around.
Next cover the top of the cake by piping the buttercream in concentric circles from the outside in. When the cake is totally covered, use a large spatula to smooth the sides and the top.
You'll see there's quite a bit of excess frosting at the top edge of the cake-you want to hold the spatula horizontally, and pull it towards the center, then upward to remove that excess.
When you've smoothed your cake all over, put it in the fridge for at least an hour, so the buttercream can firm up.
Before you coat the cake in fondant, you'll want to take one more pass at smoothing the buttercream when it's a bit more firm.