Minimum time to mix, bake and ice a cake?

[nextphase]

Hello,

If you had a chunk of uninterrupted time, and needed to make a 4 egg Victoria sponge one cake, cut in half filled with buttercream and jam), and a dozen carrot muffins, with cream cheese frosting, how long would it take? I can work out most of the timings, except for how long the cake / muffins would take to cool. What are your thoughts?

3 hrs all done and decorated without getting nasty melted frosting

In this fecking freezing weather the muffins and prob the sponges will cool outside in half an hour I reckon