My béchamel takes over an hour to thicken. What am I doing wrong?

Question

Twice I attempted to make a roux for béchamel sauce, and twice I failed.

Both times I used a ratio of 1:1, first time I weighted the butter and the flour second time I used tablespoons. First time I continuously whisked the roux, second time I mixed it with a spoon. Both times I cooked the roux under low heat.

First time, I ended up with solid blobs of butter/flour. I added my milk and cooked it for 15 minutes, it wasn't as thick as I'd like it but I was running out of time.

Second time, I didn't see the roux become white and like wet sand, it went straight into blonde. I added the milk, and it took over one hour for it to thicken. I believe the butter separated because the milk started looking yellowish. Even after vigorous whisking it still looked yellow, and it only went back to white after the milk had been cooking for about 40 minutes.

I've read multiple websites and watched countless videos but I can't figure out what I did wrong. Any ideas?

EDIT: For the sake of education I want to edit this post, because I finally figured out what was wrong with my roux (sorry if this isn't the way to do it and feel free to edit the post in that case).

The issue with my roux was the pot I was cooking with. I own mostly stainless steel pots from the same portuguese brand, but this weekend I bought a new enameled cast iron pan. I made the roux in the cast iron pan, and it turned beautifully and just how a roux is supposed to be.

Thank you to all who contributed to this thread.

Answer 1

I'm going to give you my grandma's tip:

• Start your béchamel with waaaaay too little milk; add maybe 25% of your milk
• Then let it thicken (should take a few minutes, be careful not to miss it)
• Add 25% again and wait for it to thicken, then again add the milk, etc.

You sort of quick start the reaction like this. Never failed me :)

Answer 2

It sounds to me like you aren't using enough heat. Low heat on a small burner won't even melt butter. It should take 2-3 minutes to make a roux for bechamel sauce, tops. Start with 50:50 by weight butter and flour, medium heat, as soon as the butter is melted add the flour and stir. If it's still a bit blobby add a small amount more butter or neutral oil until it loosens up. Once it's bubbly turn it down a bit and cook for a minute, then add your milk.

After you add your milk turn it way up and keep stirring (a whisk is good here) until it thickens, then turn it down. That's all there is to it.

Answer 3

Your roux isn't getting hot enough. You need to be working over at least a medium heat. Melt the butter and wait for it to get frothy - that indicates the butter is at least 100C if not higher, Then add your flour and mix - I use a ball whisk for this but whatever you have that can really reach everywhere in the pan. Note: At this point you have a "white" roux even though the color of it is going to be yellowish. That color is coming from the butter. The "color" a roux is actually describing how toasted the flour has become. So a white roux is basically untoasted flour, a blonde roux is slightly toasted, and so forth. You'd use a darker roux for things like etouffee, gumbo, and the like. Darker roux have less thickening ability than lighter roux.

If you are making a bechamel you'd use a white roux - don't cook the flour for more than a minute or so. Add the milk in a steady stream while whisking vigourously or add it in batches whisking it smooth between each addition. Bring it up to a simmer and cook until you get the desired thickness.

Answer 4

You state that you used a 1:1 ratio both times, but that the first time you weighed and the second time you went by volume. a 1:1 ratio of butter to flour by volume does not render equal weights of the two ingredients. I'm not in my kitchen to fully verify this (and also in the UK where butter doesn't come in sticks and we don't measure it in spoonfuls) but googling for the weight in grams of a tablespoon of butter and of flour suggests that a tbs of butter is about 14g and a tbs of general purpose flour is anywhere between 7.8-10g. So if your 1:1 ration, measured in spoons did not account for that, you will have only had about 55% of the weight of flour compared to butter, and this is likely the source of your problems. You also don't say anything about the volume of milk you used. I generally use approximately 9-10ml milk to each gram of flour and butter, so for 65g each of butter and milk I use 600-650ml milk, depending on how thick I want the sauce. Given that there is a limit to the accuracy of scales I always finesse the amount of milk by eye.

I wonder if part of what allowed an over-thin sauce to thicken after an our was partly evaporation of excess liquid.

I can't comment on the colour changes as I can't really visualise them in relation to my own sauce making experience and I wonder whether there is enough difference in mild and butter between your country and mine to account for that. (I only use the highest fat milk and butter I can lay my hands on for bechamel, so it is only ever shades of yellow, never white).

Answer 5

In the Joy of Cooking, they recommend baking your Roux. I have found this to be extremely effective, freeing up time to do other things while the Roux bakes. When it's baking, you care way less how much time it takes!

Answer 6

just want to share an update. I tried making bechamel again using a combination of two of the advice shared here: I cranked up the heat to medium high, and added the sauce in small batches. This definitely made it faster and easier to thicken the sauce. Thank you everyone for your tips!

Answer 7

I'm coming back here because I finally figured out what I was doing wrong. It was not the temperature of the butter, or the quantity of the ingredients, but the type of pan I was using. I was using a stainless steel pan that's apparently not thick enough for this kind of cooking. Soon as I added my flour to the butter I always ended up with this:

So I tried making the roux in an enameled cast iron pan today, and it worked just the way it should.

Answer 8

You're cooking it way, way too quickly.

I take about two hours to make roux.

(I've only ever made roux in Bourgogne, regions may differ.)