Tank Cake

My sister-in-law told me that my cute nephew lately has an obsession with tanks, so I promised her I would try to make a tank cake for his birthday. He had birthday last saturday (one day before my father's birthday) and I made three cakes for the party, this one was the only one I did without having a crisis late at night. It's a hazelnut-chocolate batter filled with hazelnut cream. On the top is a simple icing, sadly I found no way to dye the icing in a camouflage colour :( Yellow is the favourite colour of my nephew, hence I wrote his name and a four with yellow icing and used a little water to stick it to the brown icing. I think with a little more time (this week I have exams so I didn't have much time last week), I would've come up with something better. But he was excited anyway (: Here's a snapshot of him right before he blew out his candles: