I am planning on cooking steaks and vegetables in sealed foil packets on my charcoal grill and I just realized that foil can make a pretty good seal around the food. Will I be unable to get any of the smoky flavor from the charcoal if I cook using this method? Is there a way to get the flavor by poking small holes on the top of the foil, or will this defeat the purpose of the sealed packet by letting too much moisture out?
No, not really exposure is sort of the key in any method of light, and/or heavy, and/or cold, and/or hot, and/or direct, and/or indirect smoking or smoking in general. This holds true for charcoal grilling as well.
A lot of people smoke brisket covered in foil and it gets the smoke flavor but it is is also smoked for several hours.