Rub pork loin with 1/2 cup Big Daddy Seasoning and allow to sit at room temperature for 15 minutes. In a large cast-iron pan over medium heat, add 2 tablespoons grapeseed oil; Seer pork loin on all sides and both ends.
Add pork to a roasting pan with rack and roast in oven for approximately 1 hour until internal temperature reaches 155 degrees F. Remove from oven and allow to rest for 5 minutes. Slice pork very thin.
In a large pot of boiling salted water, add broccoli rabe and blanch for 3 to 4 minutes. Strain from water and shock in a bowl of ice water to stop cooking. Drain from ice water.
In a large skillet over medium heat, add remaining oil, garlic and red pepper flakes. Cook until fragrant. Add the cooked broccoli rabe. Add 2 tablespoons Big Daddy Seasoning and mix together. Remove from pan.
Assemble ciabatta rolls upside down; add provolone cheese, pork and broccoli rabe. Season with salt and pepper, to taste. Toast sandwiches for 3 to 4 minutes on each side.