Royal castle

1.Preheat oven to 170°C/340°F. Grease 2 x deep 20cm (8-inch) round cake pans and deep 15cm (6-inch) round cake pan; line bases and sides with baking paper, extending paper 5cm above sides.

2.Make cakes according to directions on packets. Divide two-thirds of the mixture between 20cm pans; bake about 45 minutes. Spread remaining mixture into smaller pan; bake about 50 minutes. Stand cakes 10 minutes before turning, top-side up, onto wire racks to cool.

3.Level cake tops. Using a 4cm round cutter, cut two half-circle recesses all the way down two sides of one 20cm cake (recesses should be towards the front of the cake). Repeat on the second 20cm cake, making sure the recesses line up exactly. (Place the first cake on top of the second cake and use the cutter to make an indent into the top of the second cake to mark the area that should be cut out­ this will help keep the recesses in both cakes lined up.)

4.To make butter cream; beat butter until white as possible, gradually beat in half the sifted icing sugar then milk, then remaining icing sugar. Beat until smooth.

5.Secure one 20cm cake, cut-side down, to 30cm (12 inch) round cake board with a little butter cream; secure remaining 20cm cake, cut-side down, on top with a little butter cream.

6.Cut one half-circle recess all the way down the side of the smaller cake. Place cake, cut-side down, on top of the cake stack slightly off centre; secure with a little butter cream.

7.Tint butter cream pale cream, reserve ½ cup; spread remaining butter cream all over the cake.

8.Using picture as a guide, make turrets by stacking 9 larger chocolate biscuits, joining each with butter cream, in each of the recesses on the larger cake.

9.Stack 10 chocolate biscuits, joining each with butter cream, in the recess on the smaller cake. Stack 9 chocolate biscuits, joining each with butter cream, on top of the cake, towards the back. Stack 5 chocolate biscuits, joining each with butter cream, on top of cake, just off centre.

10.Secure smaller chocolate biscuits for windows with a little butter cream.

11.Position jubes around top edges of both cakes, trimming to fit (we used yellow and orange jubes, but use any colour combination you like; you may need to buy more than one packet of jubes for this).

12.Trim one ice-cream wafer into a pointed door shape. Position wafer door, then position second wafer as a `lowered’ drawbridge. Use sherbet straws as drawbridge ropes.

13.Position ice-cream cones on top of each turret, securing with a little butter cream if necessary. Insert flags into tips of cones.