preheat oven to 400F.
Melt butter in the bottom of your cast iron skillet
Add brussels sprouts cut side down
Saute for about 5 minutes to brown the brussels
Remove brussels from pan, and set aside
Saute the butter and garlic until lightly browned, about 5 minutes. Be careful not to burn the garlic.
Pour garlic and butter over the brussels sprouts and toss to coat
Return brussels to cast iron skillet and place in oven
Roast for about 35 minutes.
Remove from oven and drizzle with balsamic glaze and sprinkle with salt, pepper and parmesan cheese.