Mixture for shaped cake tins

[BrandNewSlippers]

I'm making a umber 30 cake for my best friends birthday.
I've got the silicone cake tins but how on earth do I know how much mixture it needs?

The dimensions are
3- 30 x 25 x 6 Liquid volume 2l
0- 30 x 25.4 x 6 liquid volume 2.2l

Also once they're cooked should I cut them in half and put filling in them or just ice the top. The only cake I ever make is a bog standard Victoria sandwich!

You could start by working out the volume of a 6cm deep 20cm round tin - pi x 100 x 6 = 314.2 x 6 = 1885 ml or 1.885l

I make a 3-egg Victoria sponge cake and split it between 2 tins that are about 20cm in diameter, so that should work.

I'd just give it a try in the 0 tin with 3 eggs and 180g of everything else (SR flour, sugar and butter) and see how it turns out.

I work on roughly 15 sq.inches per 1 egg mix of Madeira cake. 15 sq.inches = 94sq.cm (don't worry about the depth as most cakes want to be the same depth anyway, so that rules out one of the variables).