Preheat the oven to 500°. Bring a pot of water to a boil then salt the water. Mix together the rosemary, thyme, salt and pepper. Rub this mixture all over the pork and place it on a rimmed baking sheet.
Roast the pork in the oven for around 15 minutes, until the internal temperature is 140° When it reaches 140°remove it from the oven, move pork to a cutting board and cover with foil until ready to cut.
While the pork is cooking trim the rabe and blanch for 2 minutes in the boiling water. Remove to a kitchen towel to dry it a bit. Place it on a baking tray with the crushed garlic cloves, nutmeg, hot pepper flakes, oil, and salt and pepper. Roast for 8 minutes. Flip it with tongs and roast for 5 to 8 more minutes.
The pork should be done and resting while the rabe finishes cooking in the oven. Just before the rabe is done slice the pork and transfer to serving dish, add the rabe when it is finished.