How to prepare stuffed peppers?
I pre-cook my peppers -- after I've cut them open, I let them roast in the oven for about 10-20 min, upside down (so they don't end up with a pool of water in the bottom).  I then pull them out once they've softened up a little bit, fill them, and put them back in to warm through and melt any cheese, then switch it to broil to get them browned on top.

My filling is already cooked, as I typically use leftovers such as taco meat, rice &amp; cheese. (my mom always insisted them were 'planned overs' as there are a number of dishes where we intentionally cook too much so that we'd have it as an ingredient for the next night's meal.)