You will need fresh stalks of broccoli (duh) some butter or oil, salt, pepper and whatever else you want to put on it. I use Smart Balance Light (yes, it's vegan!) salt, pepper, garlic powder and a little sugar to caramelize it a bit (and to entice my three year old :-).
Spread the butter over the top of the broccoli just like you are painting it (works very well with Smart Balance because it is soft like a margarine), I even buttered the stalk on all sides. Now, place it on a big piece of aluminum foil and salt and pepper and garlic powder the whole thing (or hot sauce or any other powdered spice you like, could try to sprinkle freshly chopped garlic on it even, but that was too much bother for me).
Now, wrap it up. Looks imposing, doesn't it?
P.S. I had to use another big piece o' foil to cover it all the way around.
Now, grill it up. I just put it on the grill (I guess it was about 400 degrees) for about 10 minutes or so per "side." (I flipped it over once). It takes a while because broccoli is a pretty tough veggie. I'd go up to 15 minutes per side, especially if your grill isn't as hot. To tell if it's done, just pierce the stem with a fork to see if it is tender and as soft as you'd like it. If not, re-wrap it and put it back on for a few minutes.
Best part? The STEM. Tastes like artichoke hearts done this way. We all fought over it.
Let me know if you try it! Enjoy! <3 Dawn