I bought one of these things and it makes perfect hard boiled eggs that peel oh so easily:
www.amazon.com/gp/product/B00DDXYC6O/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&psc=1
You do have to experiment with it initially, to find the correct amount of water to add (the cooking time depends on the amount of water you put into the device and on your elevation). In my case, the perfect result is to fill the little measuring cup they give you right to the brim, to where you couldn't get any more water in it if you tried. Dump that water into the cooker then put six cold eggs - straight from the refrigerator - into it and start it up. When the chime goes off, immediately take the eggs out and put them in a bath of cold water (this stops further cooking). Tap water from the sink works fine for me, because our tap water in Colorado comes out really cold. The amount of water you measure into the device will vary depending on your altitude, how well done you like your eggs, how many eggs you cook at a time, if your eggs are warm or cold to start with, etc. But after a few initial experiments, you'll have it down so the results are exactly what you want and are repeatable. The thing is really small and cute, maybe 6 inches in diameter. You can of course make medium boiled or soft boiled eggs too - just use less water (more experimentation will be required to learn the precise amount you need).
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p.s. - When doing your testing, start out at the high end - using more rather than less water. Then back down on the water amount as needed for your tastes. If you start out at the low end of water, you will probably end up with a couple of the first tests yielding way undercooked eggs, with runny whites. Yeuch. If you start at the high end, you could possibly overcook an egg (unlikely), but an overcooked egg is still edible. If you start out low, a wiggly glob of slime from an undercooked egg is not quite so edible.
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