Would a cake like this need to be stabilised/doweled etc? Sorry don't quite know all the correct terminology!
My base will be 10" and the top part will be 6" (but double the height of the base). Gee, I hope I am making sense.
Also any advice on less conventional means of stabilising a cake? Good solid drinking straws perhaps?
Yes--that cake will need internal support.
You will need a cake board under the behive cut to exactly the size of the cake or slightly smaller to hide the board edge. I wrap the cardboard in Press-n-Seal so it doesn't absorb moisture from the cake, get soggy & collapse.
You can get wooden dowels for support or use Bubble Tea Straws NOT regular fast food drink straws. You need the really big ones that are used for Boba Tea. I've been able to get a few from my local coffee house that sells Boba Tea.
Look for a Boba place in your town or an Asian market. They are super cheap on Amazon but you would have to pay shipping (I'm waiting to order until I have a bigger/book order).
LOTS of tutorials here & on YouTube for how to stack tiered cakes but essentially you want the weight of the top cake resting evenly on the support dowels not on the cake on the bottom.
I have use fast food straws MANY times. Particularly McD's, they are fatter for the thick shakes. My husband has walked in and grabbed a dozen or so when I was desperate and in a hurry, he just didn't make eye contact! lol Worked great!