Monday, March 5, 2012

Caramelized Onions - Sous Vide hack

After making dulce de leche, and caramelizing milk, French Onion Soup and the required Caramelized Onions was a totally logical next step.

I was worried about the "gas bloat" that affects all raw veggies when put through the sous vide process.  And with good reason.  When I looked up my favorite sous vide blog's recipe for making caramelized onions (SVKitchen) they even suffered burst bags, and resorted to double bagging.  That is one solution.

I try not to using the sous vide bags only once, especially if I don't get them very dirty, but I really hate washing them.  And reusing bags is a pain since they curl at the edges and can be tough to seal the second time.
A 2 C jar

Now onions are juicy little creatures, and will rapidly slump into their own liquid.  So they seemed like they were perfect fodder for my next test of the "jar in the sous vide" method.

chop chop chop
layer: butter, onion 1/2,
butter, onion1/2,
butter & pitch of salt

1 onion per jar
smoosh it all in

Cook the onions at 200˚F (93.3˚C) for the recommended 15 hours.  I had the water about 3/4 of the way up the sides of the jar.  So when I started there was a bit of onion above the water level.  Lids were on, and the screw bands were on loosely (about a 1/4 turn back from finger tight).

The Results... Hey it worked! 

The one drawback seemed to be the onions on top, out of the onion juice got a bit darker.  When I tasted them, they had just a hint of a bitter flavor.  This could easily be avoided in the future by pushing all the onions into their juice around 2 to 4 hours in.

Mostly... the top looks a bit dark.
I was forced to eat all the dark bits to keep them from ruing my soup.  Turns out, eating a non-dark onion with an over-darkened onion was heavenly.  I bet they wouldn't have ruined the soup at all.

1 onion's worth
From there, I drained the onion juice, and cooked the onions down to a little darker, and followed the rest of the SVKitchen French Onion Soup recipe.

Luscious soup, no popped bags, no double bags and still no oniony smell taking over the house!

P.S.  Well now its hailing!  I have the perfect remedy.


Joshua_50MF said...

This is a great idea as I don't want to double bag my onions! Have you tried using the onions for anything besides French Onion Soup? I'd like to use these as a burger topping and want to make sure the texture would work for it.

Greta said...

Joshua -

The onions will not fall apart. They are a bit wet when they come out of the jar, but giving them time in the sauté pan to dry them out a bit (and get them a bit more golden) makes them perfect for burgers, crackers and cheese, and everywhere else you can think of.
(Pizza, eggs, quiches, savory bread puddings, etc. etc. etc. They are pure gold.)