1) Bring a large pan of water to the boil. Prepare the broccoli by cleaning it and cutting off the florets. Remove any though skin of the stalks by peeling them and then, cut the stalks into small pieces. Blanch and drain the broccoli. Keep them warm.
2) Add salt and the rotini to the boiling water, and cook until it is al dente.
3) While the pasta is cooking, in a skillet, heat the oil over medium heat. Gently sauté the garlic for 1-2 min, with stirring, until soft without letting it burn. Add the drained broccoli and pepper.
4) As soon as the pasta is done, drain it quickly, and mix it with the seasoned broccoli. Adjust the seasoning and add the parmesan.
5) If desired, add green peas and mushrooms
6) Serve immediately.