Digger cake - Good Food Middle East

Ingredients

• 250g pack unsalted butter
• 50ml whole milk
• 150g whole natural yogurt
• ½ tsp vanilla paste or extract
• 3 large eggs
• 250g light muscovado sugar, any lumps squashed
• 250g self-raising flour
• 2 tsp baking powder
• 50g cocoa powder
• 2 tbsp cocoa powder
• 2 tbsp milk, plus 1 tsp more if needed
• 200g unsalted butter, very well softened
• 300g icing sugar
• 1 tsp vanilla paste or extract
• large round cake board or a large flat plate, about 13inches/33cm
• 2 plastic diggers and one dumper truck, or similar
• 9 four-finger KitKat bars
• handful Smarties or other coloured sweets
• marker pen
• 10 x 5cm rectangle of yellow cardboard
• 1 drinking straw
• sticky tape