Another idea; though you may need to present this in a baking dish. How about making a shepherd’s pie? Some versions have a pastry crust. Others are covered in mashed potatoes, which might be disguised to look like cake frosting.
Ummm…I already said “spring form” pan.
What am I chopped lamb, or something?
(Oh, sheeple)
I really think two round layers are the way to go. Remember that cakes grow in the oven, while this is going to shrink. Bread crumbs and freeze dried onions will help to keep it the same size, but it isn’t going to grow into the curves of a bundt pan. I don’t think you will get the look you are picturing from that.
This freeze dried pepper mix would look pretty and taste good in it. If you have a piping bag, you could dye some of the cream cheese “icing” and pipe little flowers on it or something. . .
Not feeling this presentation at all. 
I honestly think this will be a culinary disaster but I will be happy if proved wrong.
I think @Czarcasm should give up on this task and figure something else out. Just my $0.02.
It’s doable…
With the right binders and “icing”, that one looks great!
With the right meat, fillers, and spices, it can’t go but so wrong. Worst case it doesn’t look great, but it will still taste good.
Whoever said mashed potato “icing” is not wrong. That sounds yummy. Use a little saffron to lean in to the yellow color.