June 04, 2016
Spargelcremesuppe: German cream of (white) asparagus soup
May is Spargelzeit (asparagus season) here in Germany, and the farmers' markets are heaped high with piles and piles and piles of asparagus. Most of it is white asparagus here, with only a few options for the green asparagus that is more commonly available in Vancouver.
It is on all the restaurant menus around town, many of which have an entire special menu devoted to this beloved vegetable, which takes top billing. It's not uncommon to see asparagus with hollandaise (or Grüne Soße, Frankfurt's famous green sauce), for example, which comes with a side of schnitzel. Where else are you going to see schnitzel as a side dish? But even the restaurants that don't go all-out, will often feature an asparagus soup. Sometimes smooth, sometimes chunky, almost always creamy, and always delicious.
This recipe is adapted very slightly from the Dr. Oetker Heimatküche cookbook, our first German-language cookbook. The book notes that you can also make this with green asparagus, but that the cooking times for both the broth-making and the asparagus pieces should be reduced by two to three minutes (reduced by five minutes for really thin green asparagus).
It is a bit shockingly minimalist in its ingredient list - no onion, no garlic, no potato, no prepared vegetable stock (you make your own asparagus stock by boiling the trimmings, for enhanced asparagus flavour), while still feeling a bit involved, process-wise. It was easy, despite the multiple steps, and I will happily make this again.
500 grams white asparagus
1 litre water
1 teaspoon coarse salt
1 teaspoon sugar
200 - 300 whole milk (see below)
3 tablespoons butter
2 tablespoons flour
2 egg yolks
3 tablespoons whipping cream
Salt, white pepper, nutmeg to taste
2 tablespoons chopped parsley for garnish
Wash the asparagus very thoroughly, as it can be surprisingly gritty. Use a strong vegetable peeler or a sharp knife to aggressively remove the skin/outer layer of the stalks, keeping the heads intact. Chop off the bottom two or three inches of the stalks, and split the butt-ends lengthwise. Place the peelings and the butt-ends into a 2-litre sized saucepan with the water, salt, sugar, and one tablespoon of butter. Bring to a simmer, reduce heat to medium-low, cover, and let simmer for 15 minutes. Strain peelings and ends out of the stock (to be discarded, once cooled), and return the stock to the saucepan.
Bring the stock back to a simmer. Slice the asparagus stalks into rounds, leaving the heads slightly bigger pieces. Add the asparagus to the stock, and simmer uncovered on medium-low for 15 minutes. Strain the asparagus pieces from the stock, setting them aside to be added back into the soup later.
Measure the stock, which should be a bit less than a litre. Add sufficient milk to bring the total amount of liquid back to one litre, and keep the mixture standing by in a pitcher.
Melt the remaining two tablespoons of butter in the emptied saucepan. Add the flour and stir or whisk well, cooking until the mixture is a rich yellow colour. Slowly and steadily add the stock/milk mixture, whisking furiously to prevent lumps. When all the liquid is added, stir periodically over the next 15 minutes while the mixture thickens slightly. Do not let it boil, or the texture will become grainy.
Return the asparagus to the pot, and allow the mixture to continue to cook, over low heat, for another five minutes, stirring periodically. Do not let it boil.
Whisk together the egg yolks and cream until smooth. Using a ladle, add a little of the hot soup to the yolk mixture in a thin stream, whisking steadily, until you've added about a quarter of a cup of hot liquid. Now add the yolk mixture into the soup pot, stirring to ensure smooth integration, and let cook, still on low, still stirring a bit, for another five minutes.
Taste the soup, and add salt, white pepper, and nutmeg (just a dash - not too much!) to taste. Ladle into bowls, and garnish with chopped parsley.
This soup also purées beautifully. We had it "as is" for dinner, but the bit leftover was puréed the next day to make a starter course. I used a stick blender to puréed the cold solids (with a very little of the soup liquid) just until smooth. Then the purée was added back into the rest of the soup, stirred well, and heated through.