Simple, but excellent...

Perpare Heavy Duty foil by greasing with butter...
add in sliced 5-6 small sliced white (or red) eastern potatos (about 1/2 inch slices)... NOT Idaho's!
add in strips of sweet onions...
add in strips of red & green peppers...
sprinkle all liberally with a good Italian Seasoning mix (we really like a locally available Greek Seasoning mix)...
S&P to taste...

Roll foil into a long sealed log...
Place on the grill (or in the oven, 375-400F) for 30 mins. and turn...
cook for another 30 mins...

If you cook it in the oven, use the bottom rack position, so everything carmelizes...
We have a Weber Gas Grill, and I use the back & front burners on MEDIUM, with the center burner off...
It runs about 375-400F that way...
place the foil roll in the center, so not directly above the flame...
and you can cook your burgers, hot dogs, steaks, chicken, ribs over the direct flames on either side...