You'll find this recipe in:
Mrs. Beeton's Cookery Book
London, 1920s (?)
The Original Recipe:
INGREDIENTS. - 1 ½ pints of white second stock or water, ½ a pint of milk, 25 heads of asparagus, ½ lb. of spinach, ½ oz. of butter or good fat, ½ oz. of flour, 1 tablespoonful of cream or milk, salt and pepper.
METHOD. - Cut off the points of the asparagus and put them aside, trim the stalks and cut them into small pieces; wash and pick the spinach. Put the stock or water into a stewpan; and when it boils add the asparagus and spinach, and cook until tender (about 40 minutes); then rub through a fine sieve. Have ready a small saucepan of boiling water, put in a little salt and the asparagus points, and cook for about 10 or 15 minutes. Melt the butter or fat in the stewpan, sprinkle in the flour, add the milk and stir until it boils, then put in the stock and purée of asparagus and spinach, salt and pepper to taste, and simmer gently for about 10 minutes. Place the asparagus points into the tureen, add the cream or milk and necessary seasoning to the soup, and serve as quickly as possible.
TIME.- From 1 to 1 ½ hours.
SEASONABLE from March to July.
SUFFICIENT for 4 or 5 persons.
25 asparagus stalks
10 cups loosely packed spinach (225 g)
3 ½ cups (825 mL) vegetable stock, chicken stock or water
1 tbsp butter or oil
1 ½ tbsp flour
1 tbsp cream or milk
3 ½ cups (825 mL) milk
salt and pepper to taste (I tried ½ tsp salt and a few shakes of pepper)
1) Wash the spinach and asparagus. Cut off the asparagus tips and set them aside, then snap off the tough bottoms of the stalks. Chop the remaining asparagus into small pieces. Bring the stock or water to a boil in a large pot, then add the asparagus slices and spinach. Reduce heat and simmer until tender in a covered pot.
2) In the meantime, boil or steam the asparagus tips in a small pot. Drain and set aside when tender.
3) Once the spinach and asparagus slices are cooked, transfer these vegetables and the remaining stock or water from the pot to a blender and purée.
4) Melt the butter in the large pot over low heat, mix in the flour, then stir in 1 tbsp of milk or cream. Slowly add the spinach and asparagus purée, stirring well to avoid flour lumps. Once all the purée has been added to the pot, gradually stir in the milk, then season to taste with salt and pepper.
5) Bring the soup back up to temperature, then serve. If you're serving the soup directly into bowls, you can divvy up the asparagus tips between the bowls, or you can just add the tips to the soup.
My notes: I've made contemporary soup recipes where I pushed cooked vegetables through a sieve, so I followed the historic recipe fairly closely. I boiled the stock, asparagus and spinach for the advised 40 minutes, then tried pushing it through my "fine sieve" with a spatula and wooden spoon. It didn't work very well at all! Most of my vegetables stayed on the inside of the sieve and only a green liquid passed through. Maybe my fine sieve is finer than sieves of the 1920s? I thought it was a huge waste of nutrients and flavour to only use the green liquid, so I opted for blenderizing the vegetables and stock instead.
The spinach in this soup provides the vibrant green colour, but most of the flavour comes from the asparagus. Having the tender asparagus tips floating in the puréed soup provides a nice variety in the texture and a flavour pop to boost. The original recipe states that it makes enough soup for 4 or 5 people, but I'd say that it makes enough soup for you and a couple of friends to enjoy a soup course before your meal.
The strange thing about this edition of Mrs. Beeton's Cookery Book is there's no publication date printed inside! The internet mostly agrees that my copy is from the 1920s, generally either 1923 or 1925. Asparagus Soup is on page 69.