scaling up a mumsnet choc cake recipe - quick help please

[taffetacat]

I am about to make this mumsnet recipe as its DH's birthday today and have just realised I have 2 x 8 inch tins rather than the specified 7 inch. How much do I need to scale up the ingreds and cook time by?

Any advice appreciated

An 8" sandwich pan is 30% bigger than a 7" pan, so increase the recipe by 30% (ish). In other words, 4 eggs rather than 3. The cooking time should not be very different as sandwich sponges tend to cook from the top and the bottom. The sides won't make much difference. They are only 1/2" further away from the middle. You could leave it in for a couple more minutes but it shouldn't need any more than that.

thanks

I ended up finding a 7 inch tin and made one big one as suggested further down the page, it just needed cooking longer. The icing tbh was a bit of a disaster, had to chuck it and start over with my normal choc icing ( butter, icing sugar, melted choc, splash of vanilla and a glug of milk ).

Extremely delish, topped by DC with smarties and enjoyed by all for DH's birthday dinner tonight. Poor man - sausage and bacon pasta bake followed by Smarties cake. He had 15 years of pub crawl/curry nights out on his birthday. Pesky kids eh.