Kitchen Tip: A Watched Crockpot Does Not Cook

We have all heard the saying that a watched pot never boils, but did you know that they same thing can be said about a crockpot?

A watched crockpot does not cook the same.

Every time you open the lid of a Crockpot you add about fifteen minutes onto your cooking time. Yes, taking off the lid of your crockpot to check or stir the ingredients does slow down the cooking time.

Crockpots cook slowly. That is why they are called slow cookers and every time you lift the lid to check on your dinner you let heat escape. It takes time for the temperature to build back up after the lid is removed.

Think of it like opening an oven when a cake is baking. Every time you open that oven door you let the heat in the oven escape. The same thing applies to your crockpot.

So, be careful how many times you lift that crocpot lid while your dinner is cooking.

Do you agree with me on this one?

Lynn's Kitchen Adventures


  1. I need to print this out and show it to my husband. He is the biggest culprit. I will have to remind him the more he opens the lid, the longer it will take for dinner to be ready!

  2. Oh yes. Definitely. I find this is especially important when I’m cooking on high and the cooking time is shorter.

  3. This is such a timely post! Yesterday I was away from home at our normal dinner time so planned a crock-pot meal. As I was eating my lunch I read the same thing in a cookbook and was so surprised. It took all of my willpower to not open the lid & just walk out the door. It makes sense when you think about it, but I had never thought about it before!

  4. i so agree with you! it’s really hard not to do it though!

  5. This is so true and I’m guilty of it! My hubby is always telling me stop lifting the lid. lol!

  6. I tell my husband this ALL the time but he constantly does it…argh

  7. I haven’t found it to be true, but it’s an interesting concept.

  8. Tamara Price says:

    I am completely laughing at the other comments – and indeed it is a timely post. Yesterday I was making dinner in the crockpot and I was waiting impatiently for the last 20 minutes to be done. I set the dinner table and was all prepared for the crockpot to be done [mind you it was really hard to wait and not open the lid as I was practically pacing the kitchen] – I turned my back to get the milk out of the fridge and my hubsband walks right up to it and opens the lid to smell it. I was so irritated that he did that and told him it is like opening an oven – everytime you remove the lid you let the heat out. The event gave us a big laugh and he learned something. I am going to have to put a sticky note on the lid as the other commentor suggested.

  9. This totally boggles my mind. The physics just does not work out. The specific heat capacity of the food is so much higher than the hot air above it that it makes a miniscule difference at best. Unless the lid is left off for 5 minutes, the food inside is still cooking and the top layer may cool slightly but heat right back up within a minute.

    • Andrew Maurer says:

      Finally, a voice of reason! This is a myth.

    • Jack Puglis says:

      Sara, Thanks so much for your comment. I’ve been looking for a statement anywhere that contradicts the “conventional wisdom” that lifting the lid of a crockpot adds 15, 20, or 30 minutes to the cooking time. I strongly agree that there is virtually no effect.

      In the case of, say, a roast in ½” or 1” of liquid, the majority of the meat is not in direct contact with any warming surface. The obvious reason that the food cooks at all is that the steam generated by the liquid is a major factor in cooking the roast.

      The specific heat of water is relatively high and the steam transfers heat to the roast very well. That is the fundamental mechanism at work in a crockpot for a low liquid level.

      The liquid level stays nearly constant since the lid of the slow cooker is much cooler than the ceramic surfaces. This causes the steam to condense and drip back down into the liquid at the base. In effect, a crockpot sets up a closed water cycle.

      Lifting the lid causes a certain amount of the steam to leave the crockpot, and be replaced with cooler air. However, as you implied, the liquid is boiling and producing a significant amount of steam. The steam is therefore fully replaced in just a few minutes.

      Moreover, the specific heat of the food is also high and the thermal conductivity is low. (You can probably use a blowtorch on the end of a carrot, stalk of celery or piece of meat and hardly heat the food even one inch away!) This means that even if the lid is left off the crockpot for about 5 minutes during the cooking cycle, the food will not cool appreciably.

      I can therefore see no way in which lifting the lid adds more than 2-3 minutes to the duration of the cooking, and the reality is probably less much less than that.

      In the case where the food is covered halfway or more with liquid, the effect of removing the lid is even less.

      The converse situation, attempting to cook in a crockpot with no lid at all, is apt to fail in that the food will not be cooked in the low-liquid-level case. Any steam that is created will evolve into the room and too little heating of the food that is not in contact with the crockpot surfaces will take place to properly cook it.

      The opposite of the low-liquid-level case, where the liquid level is to the top of the food, causes lifting the lid to have even less of an effect. The liquid, heated by the crockpot, does nearly all of the cooking since the food is immersed. There is little cooking done by the steam in the space that’s left between the food and the lid.

      However, it’s important to note that the lid is still important to recycle the hot condensed liquid back into the crockpot. Removing the lid briefly though, will most likely have an immeasurable effect.

      Removing the lid and keeping it off permanently will cause each evaporated water molecule to remove the “heat of vaporization” from the meal and carry it into the air. This would serve to slow the cooking by lowering the liquid’s temperature.

      I think that part of the reason that this silly urban legend took root is because no one (or at least no one that I can find) actually does controlled testing of cooking duration vs. lid -lifts. If you are cooking in a crockpot for 8, 6 or 4 hours, how can you be sure that 15 or 30 minutes has really be added to the length of cooking?

      Psychologically, people tend to believe information that is repeated in numerous places, failing to recognize that those “places” are simply carrying the identical erroneous information forward.

  10. I disagree, the steam help cook your food and the longer u keep the lid the more your trapp the flavor and steam inside… just like cooking rice. If u open the lid to soon u let the steam out and your rice doesn’t taste the same…. goes for crock pot.

    • Jack Puglis says:

      Roam, Buddy, Please go back and read what I wrote. All you just did is to parrot the urban legend. You didn’t make any point.

      The only way to counter my post is by identifying what’s wrong with the points that I made. Simply repeating the incorrect mantra just doesn’t cut it.

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