Marinade is as follows:
3 parts olive oil (not extra virgin since we're cooking it) or butter (I prever oo)
1 part balsamic vinegar
Equal dashes (typically a teaspoon of each): ground mustard, garlic powder, Mrs Dash's, seasoned pepper, salt
I trim all of the fat off the chicken, and then just slightly slice (roughly 1/3in slices) along each side of the breast (you can sort of see this in the picture below). This way when you either pour the marinade over the chicken, or soak the meat in it, it absorbs the flavor so much better this way! I am not very good at prepping dinner a day in advance, so normally I'm doing this after 5pm to be consumed immediately, but it works just as well if you marinade it overnight. I try to let the meat sit for a few minutes while I chop veggies (bell peppers and onions, sometimes potato) to grill. For the veggies I lightly drizzle olive oil, salt, and pepper and then grill on low (I have a gas grill) for 20 plus minutes on one side or the grill while I cook the meat on medium-high on the other side. Pour remaining marinade over the meat once it's on the grill, cook for 5 or so minutes on each side, until you know it's done!
Toss a quick salad (I do spinach, romaine, tomato, cucumber, and whatever else happens to be in the fridge) and you have a great meal!
I promise it's as simple as that! The whole process takes roughly 30 minutes :-D (the best kind of meal in my opinion)