Clean off the portabella cap, and cut stem close to cap, chop stem.
Gently heat the olive oil in a saute pan, then add the peppers, onion, and stem ( I've added cubed tofu at this stage too) Saute all together until just tender Set the peppers, etc. aside for a moment and use a pastry brush dipped in the flavored olive oil in the bottom of the pan to oil the portabella cap ( both sides) Then, with the top side of the cap down, put all the peppers, etc. on the underside (up), transfer to the grill and cook for about 3-4 minutes.
Put the cheese onto of the peppers, and grill until melted.
Really good, I even like this, and I'm a confirmed carnivore! Vickie.