I think what you're looking for is what the French call an oeuf mollet. It's essentially a poached egg in consistency, but it's cooked in the shell. Very useful and not difficult. I've been working on these for a while, because I love them, and here's what I know.
1. Prick the fat end of the shells with a pin. This allows the air in the chamber to bubble out as the egg heats, and generally prevents the shells cracking during cooking.
2. The water should start at a low boil, not quite fast enough that the eggs will rattle around and crack on the walls and floor of the pan, but as hot as possible below this. Cook for 1 minute, then reduce the heat to a gentle simmer and cook 5 minutes.
3. Immediately remove the eggs from the hot water and drop -- yes, drop: you don't have to be gentle with them any more, and in fact cracking the shells a bit is good -- them into a good bit of ice water. Leave them there for at least 15 minutes. At this point you can hold them in the fridge (or in the ice water) for a good 24 hours, possibly a lot longer.
4. Shell them from the fat end, carefully, under a little bit of cold running water.
The initial high boil hardens the outer parts of the white and makes them easier to shell. Reducing the heat after a minute helps the egg not get rubbery and sulfurous. The yolk should be very creamy and liquid when you cut into it, like that of a properly poached egg.
Suggestion for eating: nestle them in a big dish of cooked Swiss chard, cover lightly with a thin bechamel, sprinkle generously with grated Swiss-type cheese (Gruyere, Emmenthal, etc.), and run under a broiler for a couple of minutes until the top is brown and bubbly. In general you can treat the peeled eggs as you would a poached egg; to warm them by themselves, drop into gently-boiling water for 1 minute and proceed from there.
