Prepare a marinade the day before and let it steep for at least 5 hours.
Pat the pork dry, remove any tendons and silver skin, and place in a zip-lock bag. Add the marinade to the bag, press out air, place the bag in a bowl, and refrigerate for 4-6 hours.
Heat a pan over medium-high heat and add about 2 tablespoons of the marinade oil. Season the pork with salt and pepper, then brown on all sides for 2-3 minutes per side.
Preheat the oven to 110°C (230°F) with top and bottom heat. Place a casserole dish inside to preheat.
Sprinkle about 2 teaspoons of Provence herbs on a board and roll the browned pork thoroughly in the herbs to coat all sides.
Place the pork in the preheated casserole dish and roast in the oven for 55-60 minutes. Turn off the oven and allow the pork to cool inside for at least 3-4 hours until it reaches an internal temperature of 63°C (145°F).
Remove from the oven and slice to serve as cold cuts.
Optional: For a warm main course instead of cold cuts, roast for approximately 15 additional minutes before turning off the oven to cool.