I know i can freeze the fondant covered cake , but how can i freeze the smbc covered cake? I dont have that much space in my freezer , so can i only wrap around the cake with saran as covering the ganachhed covered cake ? Or should i put it in the cardbox as the fondant cake Thanks
Once the iced cake is cold enough that the icing has gone hard, I would suggest carefully smoothing plastic wrap over all the exposed areas to help preserve the flavour and to prevent it from being tainted by anything else in the freezer. If it's fully covered in a couple of layers of plastic wrap, I don't think you would need to use a cardboard box as well, other than for protection.
When thawing and bringing the cake back to room temperature, remove the plastic wrap immediately, or you'll end up with a messy buttercream surface if you try to do it once it's warmed up. Even so, you still might have to do some touch-ups, as any folds in the plastic wrap may leave small marks.
Disclaimer: I've never frozen a SMBC-covered cake, so I'm just going by gut instinct...it is what I would do based on my experience with freezing SMBC by itself.
ACan I ask why you are freezing it? Are you trying to work ahead or saving/storing for a long period of time?
If you want to save a wedding tier for example, then I would place in a box as well as wrapping.
If working ahead I wouldn't recommend freezing the iced cake. You can freeze your cake wrapped in plastic/foil and you can even make your BC ahead and freeze.
AIf I bake ahead and freeze, my cake for example, I wrap in plastic & foil. I leave my cake wrapped until it starts to thaw at least halfway so the condensation forms on the foil/plastic rather then my cake. Personal preference :)