From Mark Bittman's How to Cook Everything Vegetarian.
This is a quick and delicious side!
3 tbsp butter or olive oil
1 lb. Brussels sprouts, hard edge trimmed off of stem,
and loose leaves removed
1/2 - 3/4 cup vegetable stock, white wine, water, or vermouth
salt and pepper to taste
fresh Parmesan to taste (optional)
Mix sprouts, butter, and liquid in a skillet, sprinkle with salt and pepper, and bring to a boil. Cover, reduce heat, and simmer until sprouts are tender, 5-10 minutes. Add liquid as needed.
Remove lid, and raise heat to boil off the liquid. Don't stir much; you want the sprouts to brown slightly and to acquire an (uneven) coat of glaze.
Optionally sprinkle with grated Parmesan, to taste.