So I'd often wondered whether my little Sunpentown countertop induction cooktop could double as a sous vide cooker. After asking for it as a wedding present (and then buying it for myself when nobody thought it substantial/romantic enough), I've never really found a great use for it except as an extra warming plate when in a pinch, or a way to boil rice or pasta in the summer while keeping the house cool.
I did some experiments with just water and my digital thermometer. (Not to turn this into an endorsement-fest, but I love, lurve, this thermometer. It's exact, durable, and easy to use.)
The first experiment, I set it on "cook" and set it for medium-low, which the cooker said was155 degrees F. Well, I don't know what that means in Taiwanese, but it doesn't mean "make the water 155 degrees." It means, "boil the water, but not as quickly as on medium." Realizing that I had to go rely only on my observations, not the assertions of the cooker, I redesigned.
The second experiment, I put 8 quarts of water at 155 F on the cooker on its low warm setting. "Warm" doesn't appear to mean anything other than, "cycle on and off at regular intervals". Well, lo and behold, the water slowly came down to 144 F and stayed there. Or looked to stay there. I had to go to work... Yes, I was doing this in the morning before work... What? Oh, like you've never done a little science in the morning just to get the day going.
Tonight, I took hot water from the tap, filled up the pot, put it on low-warm and left it, taking the temp every 20 minutes. It came up to 141.5 and stuck there, which is not enough for a "perfect egg", so I put it on medium-warm and it jumped to 155 for a couple of minutes before I brought it down quickly with a glass of water. I found that by half-covering the top, I could get it to come up to 144.5, which is perfect for eggs.
Here's the result, with chopped thick-cut bacon, on a toasted baguette.
Here's what happened when I broke the yolk.
This was... well, this was just stupidly delicious and amazingly easy. Here's the delicata squash soup with fried sage leaves I made while the "main" course was cooking.
Being limited to 141 or 144 degrees is not ideal, but given that I have the equipment around anyway and it's easy, why not, right? With those temps, I can make eggs, beef, pork, and chicken. I'm thinking of pointing a fan at the open top of the pot to see if I can get it down in the right range to do fish.
UPDATE:
I never did this again. I've since been using my Nissan Thermos Vacuum Flask Cooker for all sous vide cooking.