Put everything except chicken in a blender or processor, and whiz until smooth
Put breasts in a ziplock bag with a tablespoon or so of oil, close up and pound to an even thickness - ½ inch would be great
Add most of the marinade, seal and refrigerate at least a couple hours
Remove from fridge about 30 minutes before cooking, and heat grill to medium high
Cook breasts, turning every couple minutes, but making sure to get good grill marks
You can start basting it when it nears 150 degrees, then pull off the grill at 160 - it'll continue to rise a few degrees
And that's it sparky, away you go