The first station I was assigned to on the pastry side was Cakes and Tarts. For those of us on the station, our daily task was to come up with 48-60 plates of dessert. Which sounded impossible until I learned that each cake yielded 10 slices (or 10 plates), and each pie/tart 8 slices. So each day we made some combination of cakes (including cheesecake or moussecake), pies/tarts, and tartlets.
Being that the previous pastry people had left us with a surplus of cake rounds (chocolate, vanilla, devils food, carrot, etc.), all we really needed to do was assemble them. So we got a crash course in cake-decorating.
First we defrosted the cake rounds (generally two for each cake we built), filed off the tops and basted the exposed cake-ness in simple syrup. Then we frosted them with buttercream. For the first one we made, we decided also to add strawberry slices (being that the cake was vanilla).
We quickly learned that buttercream frosting needs to be at the right temperature (and thus consistency) for it to frost nicely. If you look closely at the picture you'll see the unevenness and the crumbly edges that were the result of dragging too-congealed buttercream across the cake surface.
Once the upper layer was added, we frosted it all over the first time, which is known as the crumb coat. This is because the crumb (general term for the innards of any pastry) is still exposed and crumbs (haha) generally come off with the excess buttercream that is scraped off to make the layer smooth. After this first layer of frosting the cake is then put in the walk-in refrigerator for a bit so the buttercream can solidify, yielding a smooth layer for the final frosting.
Being that this was our first attempt at cake-assembly, the cake was still bumpy-looking after the final frosting (or, as Chef Mark put it, "homely-looking"). As an improvement, Chef demonstrated using the triangle-teethy tool (one of the many specialty tools I know not the name of) to create wavy lines of distraction all over the cake.
And voila! First cake assembled.