Step 1

Preheat oven to 180°C/350°F. Grease 20cm x 30cm (8-inch x 12-inch) rectangular cake pan; line base and sides with baking paper, extending paper 5cm (2 inches) above sides.

Step 2

Make cake according to directions on packet; spread mixture into pan. Bake about 30 minutes. Stand cake in pan 5 minutes before turning, top-side up, onto wire rack to cool.

Step 3

Level cake top; turn cake cut-side down. Using picture as a guide, cut clock from cake. Secure cake, cut-side down, on cake board with a little butter cream.

Step 4

Using round cutter as a guide, mark a circle on top of the cake to represent face of clock. Place one-quarter of the butter cream in small bowl; tint pink. Stir combined sifted cocoa and the water into remaining butter cream in medium bowl until combined.

Step 5

Spread pink butter cream evenly over face of clock, continue down body of cake to within 4cm (1½ inches) of cake edges, as pictured. Spread chocolate butter cream evenly over rest of cake. Outline cake with chocolate-covered bullets. Outline pink section with Smarties.

Step 6

Spoon remaining chocolate butter cream into piping bag; pipe numbers on clock face. Cut thin strips of licorice and position on cake to make hands of the clock. Using picture as a guide, use thin strips of licorice and freckles to make the pendulums.

Step 7

To make and decorate mice, cut 2 Smarties in half; push into prunes for ears, secure with a little butter cream, if necessary. Cut thin strips of licorice for tails and thin strips of snake for whiskers; secure to prune with a little butter cream. Position mice on cake.