While you are bringing 3 quarts of water to boil to cook the pasta, chop the onion and slice the garlic. Have the rest of the ingredients close at hand and you are ready to go.
When the water comes to a boil, add the orecchiette, cook for 8 minutes. Add the broccoli rabe and continue cooking for 8 minutes.
In the mean time, add olive oil to a large sauté pan and cook onions over high heat for 6 minutes.
Add garlic and chili pepper and lower heat.
Drain the orecchiette and broccoli rabe, reserving ½ cup of the cooking liquid.
Add orecchiette and broccoli rabe to the sauté pan along with reserved cooking liquid.
Add nutmeg, salt, pepper and Parmesan cheese.
Toss well and serve.