Level off all your round cake layers. Use a long, serrated knife and use a smooth sawing action to take any bumps or domes off so you have nice flat surfaces to work with. Save the trimmings and use them another day for cake pops - I keep the bag of offcuts in the freezer

Take a 10" layer and put it cut side down on a cake board

Coat the top and sides with 3/4 of the chocolate frosting

Put the cut side of the other 10" layer directly on top and coat only the sides of it with the rest of chocolate frosting

Take a quarter of the plain white frosting and add some green gel colouring. Mix well and add as much as you want for the shade you like. I like the Wilton gel colours as they don't dilute your frosting and make it runny

Spread the green frosting over the top to meet the chocolate sides, it's meant to be grass so it doesn't have to be neat or perfect, none of this does!

Take another quarter of the plain frosting and add blue colouring, again to the shade you like best

Set the 8" layer on a cake board and go around the sides with the blue. Again it doesn't need to be neat, we're going for a hard icy look here and a choppy finish makes the ice look sharper. I tear squares of parchment paper and wedge them under the cake so once it's frosted you can remove them and the board is still clean.

Gently lift off the board and centre on top of the 'grassy' cake and spoon some plain white frosting on top. You can patch where you lifted the cake easily with some extra frosting

Like the 'grass', spread the 'snow' out to meet the 'ice'

Instead of placing these in the centre of the lower layer, place them towards the back of it so you give yourself a larger space at the front to fit in the stairs

Now take 2 or 3 slices of the loaf tin cake (I cut mine into 10 and froze the other slices for another day) and trim into a neat rectangle. Slice your rectangle into 3 even pieces

Start to build your stairs from the bottom layer up. Some steps you'll need to overlap and trim to fit. Use your eye to gauge