I just got 15 chicken breast from my butcher, each weights approx. 2lbs. The ones I usually get are 1 pound each. I will be bbq on a large grill which I pull behind my truck. Should I cut slits on the top of each breast to insure even cooking??
Why not cut them in half diagonally?
I am always reluctant to cut a piece of meat like a chicken breast prior to cooking...especially grilling. One of the ways I like to grill chicken is to first do most of the cooking in the oven. I season the breasts and thighs under the skin (a little herbed butter) and the outside with some salt and pepper. Then roast them until they are virtually done, within a few degrees of the desired internal temperature. Then finish them on the grill to bring the internal temperature up those few degrees. The grill is mostly for crisping up the skin and adding a touch of the fire flavor. In all, I have to put up with much less in the way of flair-ups because much of the fat is rendered out during roasting, I don't have to pay attention to the grill for such a long time, and all the pieces are equally done because there are fewer cool spots in the oven than there are on the grill.
If you are going to drag that grill somewhere with your truck, then maybe I'd think about roasting the breasts beforehand and chilling them in the 'fridge. Then keep them cool on the way to wherever you are going. Once the grill is set up, oil the grates and bring them up to temperature over low/moderate heat with the cover closed.
Be sure to let us know what you end up doing and how it went!