Put the filling in between layers of the cake. Make sure to pipe the perimeter of the cake with buttercream as a guide of the thickness of your filling, and as a protection to stop the filling oozing out of the cake.
Spread the filling, and make sure it's level with the buttercream guide. Now you have your filled cakes. Carve the cake to your desired shape; in my case teacup.
Coat the cake with a thin layer of buttercream; this will help keep the crumbs intact (hence, crumb coating).
Chill the cake until the buttercream doesn't smudge on your fingers when touched; maybe around 30 minutes.
Do the second coating of buttercream. This time thicker, and the purpose is to shape the cake as perfect as you can, so as to make a nice smooth silhouette once the fondant is draped over.
Make sure to chill the cake until the buttercream is set before covering with fondant.
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