(Note: To make your own coarse ground pork, buy 1 1/2 pounds of pork shoulder or butt and cut into chunks. Add to processor and pulse-grind into a coarse chop.)
Heat a tablespoon of EVOO, 1 turn of the pan, in a large, heavy-bottomed pot over medium-high heat. Add pancetta and brown a couple of minutes then remove to a paper towel-lined plate to drain.
To the same pot, add another tablespoon EVOO and heat until oil smokes. Add pork and brown a couple of minutes over high heat. Reduce heat a bit and add in garlic, fennel seed, crushed red pepper, paprika, cayenne, cloves, salt and pepper. Cook 3-4 minutes more then remove and add to the plate with reserved pancetta.
Add remaining 2 tablespoons EVOO to the pot over medium heat. Add in peppers and onions, season with salt and pepper, and cook 10 minutes, stirring frequently, until tender. Stir in tomato paste, cook 1 minute then stir in wine. Cook 30 seconds to burn off the alcohol then add stock to deglaze. Add tomatoes and mash them up with wooden spoon or potato masher then stir all the reserved meat back into sauce. Simmer to thicken over low heat, stirring occasionally, for 30 minutes. Stir in basil.
While the sauce simmers, bring a large pot of water to a rapid boil for the pasta and make besciamella: In a sauce pot over medium heat, melt butter. Whisk in flour, cook a minute or 2 then add milk and cook until it's thick enough to coat the back of a spoon. Season with salt, pepper and nutmeg.
Place rack in center of oven and preheat broiler.
Cook rigatoni to al dente in salted water. Drain and toss with thickened ragu and place in a casserole dish.
Remove besciamella from heat and stir in provolone to melt. Pour sauce over top of casserole in a thin, even layer. Place casserole in oven on center rack and brown. Top with parsley and serve.