Michelle Darmody: How to bake a classic chocolate sheet cake — and the mistakes to avoid

"The chocolate ganache topping is a great thing to have in your repertoire and can be used in anything from making chocolate truffles to icing buns or filling tarts."

With a sheet cake, you have the bonus of a large canvas which can be drawn on, or decorated, for a celebration event.

Sheet cakes or tray bakes — whichever words you want to use — are very handy for occasions when you need to cater for large groups. 

Baking a cake in one solid rectangle makes it much easier for slicing and storing than a taller, circular cake.