Melt one ounce of butter into a saucepan, add one large dessertspoonful of flour, cook well, but do not brown. Add three gills of milk, one medium-sized cucumber, peeled and cut into slices, one ounce of proteid food, and salt and pepper to taste. Let it cook until the cucumber is tender, pass through a wire sieve, and add a little green spinach colouring. Add a little more milk if the mixture is too thick.