Par-Cooking Corn on the Cob in a Microwave

The best way I have found is to soak the ears in husk for several hours before grilling. This lets the husk soak lots of water. Then place the corn, still in husk, on a hot grill for about 10 minutes, ~1/4 turn, 10 minutes, turn... until the husk gets brown, even burnt.

You should be able to tell when the corn is cooked by the smell. The sugars in the corn will start to caramelize and brown in the husk and it will give off a delicious caramel smell. You can check them by peeling down the husk to make sure that they are cooking well.

Times will depend on your grill and how much patience you have. In general, it is difficult to overcook. You want to watch out for drying, but that usually takes a while if you soak the ears beforehand.

Foil is a poor substitute for the natural wrapper. The husk both protects the cob from too much direct heat as well as holding water close to the cob to gently steam the kernels. And its just prettier with the browned and burnt husk, au natural.

I've done it in the husk, when it's fresh (ie, the husk isn't dried out), but I don't like the grassy flavors that the husk imparts.

My neighbor's clued me into a box of dry wax paper sheets to cover food for the microwave (so I can be lazy and not have to clean the microwave as often), so I wrap the corn in it after it's been husked and the silk removed. I just roll in around the corn, twist the ends like the paper wrapping on taffy, then microwave it for a few seconds.

I haven't done it recently, so I can't remember exact times (and the wattage of microwaves differ, anyway) ... you just want to warm it through, though. If you were going to try to get it hot, I'd consider dropping to medium power for a much longer time, so you don't overly cook the outside, as I vaguely recall having an incident once.