Having never actually seen a Tiffany box, because I live in Australia and we don't have Tiffany here, she was wise enough to send me a web pic of what she wanted. This was really useful although the resolution was poor and I couldn't really see how the middle of the bow worked. It was also (I'm guessing) a full-size cake, and it is much harder to do miniature designs. I told her straight out that I wouldn't be able to do the printed text, but this wasn't a problem for her, so I decided to give it a try!
I started by cutting a 7cm square piece from a larger ganached square cake, then I ganached the cut sides and hot-knifed it to be square around all the edges.
Then it was time to roll out some tinted blue fondant and cover the cake... and I discovered my first mistake. Because I had not covered many square cakes before, I didn't realise that the perfectly hot-knifed, SHARP edges and corners of the cake might tear the icing - see here it's starting to go in the right front corner?
I pulled the icing off and discarded it, then went back to my cake. This time, rather than squaring the corners off with a spatula, I gently rubbed all the edges and corners with my finger. The small amount of heat transferred began to soften the ganache, and I was able to create slightly rounded edges, which were able to be covered much more successfully.
Next came the bow. I rolled white fondant and cut it into centimetre-thick strips with a ruler and a sharp knife.
I stuck the 'ribbon' to the cake, then used the same thickness and size of fondant to make the bow for the cupcake.
Here are the bows. I did two cakes, thinking that I would be able to give my friend the best of the two and keep the other.
I'm really glad I did, because in making the second cake, I tore holes through the icing in one side. After working on this and trying to fix it for ages. I decided it would be better off hidden under a bow, and kept for myself - This result just wasn't acceptable.
This was my workspace halfway through proceedings. Your can see my referral image on the iPad on the right, and the cake with ribbons on but bows still not attached, on the left.
End result: a box within a box - a fun project and it's always great when you can make other people happy too!