1. Bring 1/2 gallon of salted water to a boil. Cook broccoli florets and pearl onions separately in the boiling water until just tender, about 3 minutes for the broccoli and 8 minutes for the onions.
2. Cut the onions in half.
3. In a shallow pan, heat the oil over a high heat. Add the onions, salt and pepper and cook for 1 minute. Add the mushrooms and cook for 2 more minutes. Add the broccoli and cook 2 more minutes.
4. Adjust the salt and pepper to taste. Serve immediately.
Serving Size: 1/2 cup