Does anyone know how long in advance I can make a sculpture from rice krispie treats and cover in sugar paste, before it goes off??
A very loooong time. You should be fine to make it even weeks in advance.
how do you make the RKT smooth so it doesn't show through the fondant covering? I tried once but the sculpture appeared all bumpy!
Once I have it sculpted, I use a rolling pin or something hard to smooth out the bumps from the cereal- I've even used a hammer before (obviously I am not a professional ) but also- you should frost the sculpture with buttercream before putting fondant on it.
Thank you Debbye27!! I will try the rolling pin to smooth it... have to make some legos and cover them in fondant.