I could've sworn that the fail-proof way to cook perfect (as in no dark rings around the yolk and no stick egg whites) hardboiled eggs was to fill up your pot with cold water and slowly submerge the room-temp eggs (making sure the water is at least 1" above the eggs). Then wait for it to start boiling then take it off the flame and cover with a lid and wait 15 minutes. As you can see, this technique kind of failed. Any fool-proof techniques out there??