Welcome to the Cake Decorators Q&A

Can I use modelling paste instead of marzipan on a sponge wedding cake?

Hello EstherB

I am assuming that the cake has been crumbcoated with buttercream and not ganache? If this is the case a good substitute for marzipan is a thin layer of sugarpaste and then cover as normal. Let the first covering dry before applying the second cover. You could also use half chocolate modelling paste and half sugarpaste kneaded together. Hope this helps and that I’ve understood your question accurately.

Thank you for your advice. I hadn’t considered that. Another cake decorator advised a good crumb coat, fridge overnight then cover with about 4-5mm thick sugarpaste – a good brand. What do you think? I use Massa Ticino for my cakes.

That would work too as long as the buttercream crusts really hard to make a very firm platform for the sugarpaste. For crusting buttercream use more icing sugar to butter ratio or for an alternative recipe look here:
http://www.cakeflix.com/online-cake-decorating-courses/rustic-wedding-cake-by-vs-cakes
Scroll to the ingredients list for the recipe.
How about using ganache instead of buttercream? Ganache tastes absolutely fabulous and sets as a shell to provide a lovely smooth surface. Ganache quantities charts for filling and covering and for different chocolate types take a peek here: http://www.cakeflix.com/carry-on-ganaching-new-charts-and-recipes

Hope this helps.