How to thicken everything including how to make a roux and how to thicken without fat

Those of you who regularly read my blog know I am attending culinary school (I've got another blog about that if you want to see: There are challenges galore including, sigh, having to eat meat (I just went through a huge personal battle with pork).

But, one of the bonuses of going to culinary school is I'm learning all sorts of great tricks. Like how to thicken soups and sauces and anything else you want to thicken. Easily. Both with and without butter.

Now, I promised I'd share any good tips I learned there with you, so here we go ... some of the handiest culinary tricks around.

Technique #1: Roux
Roux is a mix of equal parts (equal parts, as chef put it, “By weight, my friends, by weight.”) of fat (typically butter) and flour (usually all purpose) cooked in a saucepan. There are four types of roux: White, blond, brown, and dark. White is cooked for 2 - 3 minutes, until it turns a creamy beige. Cook 4 - 5 minutes instead and you will have a blonde roux which, most interestingly, smells like popcorn. Brown roux takes a bit more time. And dark roux as much as 15 minutes or more.

Okay. So I bet you are wondering why you are making a roux. Well, this stuff is used to thicken your sauce or soup. And, most interesting, the lighter the roux, the better it is at doing this.

Now, you have to cook your liquid for some time after you add your roux to get rid of the flour taste. Blonde rouxs have to be cooked for at least a half hour after adding your roux. A dark roux, on the other hand, needs a cooking time of at least an hour. And remember to add roux sparingly to your liquid. See, this stuff does not start to thicken until your liquid is brought to the boil, so if you add too much too soon, you might add too much.

Remember, it is easier to add than to take away.

Technique #2: Veloute sauce
Veloute means velvet in French. And this is what gives those professional soups their velvet taste.

This is so easy to do: You simply whisk, bit by bit, some roux into your vegetable stock, making sure to whisk away any lumps. Then you leave your stock on very low heat for, say, 45 minutes or so to thicken.

This makes a veloute sauce which you add to your soup to thicken it up.

Technique #3: Sweating vegetables
The tough part about seating vegetables is finding a sauna that will accept them. Naw. Only kidding!

Okay, there are two things you can do to vegetables: Sweat them or caramelize them. Caramelizing is where they turn sweet and brown. When you sweat them, you do it nice and slowly (and low, low heat) so they soften without caramelizing. This is how you do it using a classic mirepoix (a very tasty mix of vegetables, classically 2 parts diced onion to one part each diced carrots and celery):

  • Heat your pan.
  • Add your fat and melt it (fat can be butter or oil, but if you are going to use an oil, use one with a high smoke point such as canola oil instead of olive oil, so it doesn’t break down on you). Of course, you are free to substitute stock for the fat if you want a fat-free version.
  • Add your densest vegetable, first, because it takes longest to cook. In this case, add your carrots.
  • Lower your heat; remember, you are not caramelizing here.
  • Once you smell your carrots, add your celery.
  • Smell the celery? Then add your onions.
  • And don’t forget to stir.

Vegetables nice and soft? Then go ahead and pop them in your blender or food processor to make a puree. Which you can now add to your soup or whatever you like for instant thickening with no fat and extra taste.

See how great culinary school is?!