Beat all together adding 1 teaspoon mustard.  Boil slowly like omelette, let cool.  Chop up fine 1 stick celery, couple lettuce leaves, parsley and cress.  Spread cheese paste on bread, well buttered, sprinkle on helping of lettuce and make into sandwiches.  These are delicious, cheap and very appetising.

From

The Housewife's cookery book and shopping guide. 5th edition.