Asparagus Soup

If you said "asparagus soup" to me, I would probably yawn and go back to searching for a good recipe for butterstoch-miso or chocolate parmesan gnocchi. At this point I have to realize I've completely lost touch and need to come back to reality. Asparagus is a wonderful spring flavor and a king among vegetables. It deserves to star in its own dish and not just take second stage to beef or chicken.

I was looking at an old recipe I wrote for a chilled green asparagus soup and it got me thinking about how I would make it today. The fact that its a green vegetable is really what drew me back to the idea, because care must be taken to preserve the color. I start to get a little more excited when I think there really is no cooking past the stock and the asparagus destined for puree.

At this point I'm engaged in a brainstorm focusing solely on my methods. It has actually been quite a challenge to completely omit, garnishes, flavor combinations etc from this thought process.

We can break it down and focus on the elements. A vegetable soup is basically a vegetable puree that has been thinned with a water-based liquid to a soup consistency.

So we have 1) the liquid and 2) the puree. So how can we infuse and preserve the flavor of the asparagus, at the same time controlling the heat to preserve the nice emerald green color?

We can infuse the base liquid or stock with the woody end of the vegetable and the peelings that we normally discard. We can steep the liquid with raw asparagus. We can use the raw juice of the vegetable.

Asparagus juice

Juice the stalks in a juicer over an ice bath. We could always juice white aspargus and reduce it down.

Asparagus Stock

vegetable, chicken or bean stock
mirepoix and herbs
parmesan rind
whole coffee bean (3 per liter)
asparagus, woody ends and peelings
thinly sliced raw asparagus

bring the stock, mirepoix, woody ends and peelings up to a boil and cook 10-15 minutes. Strain over the sliced asparagus and allow to steep another 10-15 minutes. Strain again and cool completely. Save the asparagus juice for the finished soup.

Asparagus Puree

Normally we would blanch the asparagus in heavily salted boiling water and shock it in ice water. There are a lot of aromatics and flavors lost in this process. I don't want to completely eliminate the cooked element, but how much do we really need to cook it to make a puree? Can we sous vide it for a very short time and use the pacojet? Pressure cook it? Pressure cook it sous vide? If we can boil the asparagus in a bag, we can save all those nutrients, but it may discolor before its cooked in time.

Use the asparagus stock and juice to thin out the puree to a desirable soup consistency. But we can still add more flavor. Since we are not reheating the soup, we can cold infuse it with more asparagus and herbs.

Cold infusion

thin sliced asparagus
herbs

Add the asparagus and herbs to the finished soup and cold infuse until the soup is ready to be served. Strain and serve.

Is this the best I can do? What about asparagus powder? Can we use a gastrovac to reduce asparagus juice without heating it enough to discolor?