Give the poblanos a good rince under water. Cut off the tops just past the stem and save the tops for garnish later. Pull out the seeds and rince the insides with water. Use a spoon and push the mixture into the pepper. Really stuff it in there, don't be shy about it. the rice should be the glue that holds everything in and the pepper will loosen up a little while it grills. When all the peppers are stuffed, head back out to the grill. Coat the peppers with the olive oil and place them over direct heat. Give them about 10 minutes a side or until they char a little. Some charring is a good thing here.
If you have some squash, you may want to throw it on during the poblanos cook time for a side dish. Squash coated with a little garlic olive oil and grilled = pure awesome.