1 bag of cipollini onions, peeled
Preheat the oven to 400F. Spray some non-stick spray or lightly butter a piece of aluminum foil and put it over a baking dish.
Spread the onions on to the foil and drizzle EVOO and balsamic vinegar on top. Season with S&P. Sprinkle a few thyme leaves or entire sprigs over the onions.
Roast in the oven 20-30 minutes or until soft enough you can easily poke a fork through them.
Add a little more EVOO and balsamic vinegar at the end if they look too dry.