Mushroom Soup - 1930's

Don't eat these mushrooms, buy them from a shop.

Its cold outside, the perfect soup weather.  Mushrooms have an earthy savory flavour that is perfect in a soup, and added with onion and scattered with some lovely crispy croutons, you're on to a satisfying vintage recipe your grandmother would have loved, assuming she liked mushrooms.
We now have pre-made croutons available to us, so a quick fix is available.  But in my opinion you cannot beat home made croutons.

2 pints of white stock
1lb mushrooms
2 eggs
1 Spanish onion
1 dessertspoonful of flour
A little milk
A little cream
salt and pepper
Croutons of fried bread.

1. Wash the mushrooms and chop them up.   Chop up the onion finely then bring the stock to the boil.
2. Add the mushroom and onion then boil for half an hour.
3. Pass all through a tammy or a fine hair sieve.  Add a dessertspoonful of flour mixed into a smooth paste with a little milk and salt and pepper to taste.
4. Boil up again, and just before serving remove teh soup from the fire and add the yolks of two eggs beaten up in a little cream.  Do not let the soup boil after adding the eggs, just enough to thicken the soup.
Serve with croutons.