I read an article about Asian cooking involving a Vacuum Flask so I was looking for some techniques involved in cooking with it. 
I've had excellent results using my vacuum flask cooker to do slow-cooked eggs. Also known as 63° eggs because they're usually sous vide cooked to 63° C. These eggs are a feature at fancy restaurants all over New York.  Here's a picture of a dish from Eleven Madison Park:       from my favorite English-language Japanese cooking blog, justhungry.com   Provided you have the equipment (vacuum cooker, thermometer) and your tap water is hot enough, these eggs could not be easier. You do them without even turning on the stove.   Put four or more eggs in a bowl. Run your tap water on hot until it won't get any hotter. Take a temperature reading and make sure your hot water is hotter than 64° C (147° F). Don't worry if it's much hotter than this. That's actually good. Cover the eggs with hot tap water. Fill the vacuum flask cooker a quarter of the way with hot tap water and close. Go do something else for 10 minutes. (Boil the pasta?) Run the tap again to get hot, dump the water from both bowl and cooker. Fill cooker 2/3 way with hot tap water. Put eggs in the cooker. (I use a steamer basket to keep them suspended in the middle of the water, but I'm not sure it's totally necessary.) Take a temperature reading and adjust the water to 64° C (147° F) by adding cool water, if necessary. After 30 minutes, take the eggs out with a slotted spoon and crack them over whatever you want to make more delicious.  