exercises

15. task models

EXERCISE 15.7 [extra - not in book]

Look at the recipe for Chocolate Biscuit Cake. Produce a hierarchical task analysis (HTA) based on it. The recipe considers only the most basic actions and you will have to determine higher level tasks. Also, the recipe may give a specific order for some sub-tasks which could in fact be performed at the same time or in a different order. Finally, the recipe may omit various details assuming that the cook will know what to do.

Expand some parts of the recipe to as much detail as possible.
Make a list of all the things you need to know about in order to follow the recipe
If possible, compare your answers with those of others. Did you notice different things?
NB It makes a very nice dessert.

Chocolate Biscuit Cake

Metric Imperial
225 g plain chocolate 8 oz plain chocolate
225 g butter 8 oz butter
2 eggs, beaten 2 eggs, beaten
25 g caster sugar 1 oz caster sugar
225 g digestive biscuits 8 oz digestive biscuits

Grease a 15 cm (6 in) cake tin with a detachable base. Break up the chocolate and put it in a bowl over a saucepan of simmering water to melt. Melt the butter in another pan over a low heat. Beat the eggs and sugar together in a bowl. Pour the melted butter in slowly, beating all the time. Now blend in the melted chocolate. Break the digestive biscuits into small pieces and fold them into the chocolate. Put the mixture into the cake tin and chill overnight, in the refrigerator. Turn out of the tin and serve.

answer available for tutors only

open-ended investigation

Other exercises in this chapter

ex.15.1 (ans), ex.15.2 (ans), ex.15.3 (ans), ex.15.4 (ans), ex.15.5 (ans), ex.15.6 (tut), ex.15.7 (open), ex.15.8 (open), ex.15.9 (tut), ex.15.10 (tut), ex.15.11 (tut)

all exercises for this chapter