Pre-heat oven to 400 degrees. Cut ½ inch off the top of the garlic head, place in a piece of aluminum foil, drizzle cut end of garlic with olive oil and sprinkle with a pinch of salt. Wrap tightly and place in oven for 20 minutes. Remove from oven and when cool enough to handle, squeeze the garlic cloves from the skins into a bowl and mash. Finely chop herbs and combine with peeled, mashed garlic cloves, salt, pepper and 2 tablespoons olive oil.
Lightly sprinkle all sides of the pork with salt and a few turns of fresh black pepper. Sear the pork in a skillet over very high heat in a little olive oil until just lightly browned all over, about 5-7 minutes. Remove from heat and let cool.
When the pork is cool enough to handle, evenly coat the tenderloins with the garlic herb mixture. Tuck the tail ends of the loin under so the pork is an even thickness. Wrap bacon around herb mix coated tenderloins so the ends of the bacon are underneath the pork; tie with twine. Return the pork to the skillet and sear in olive oil on all sides over medium/high heat until bacon is golden.
Place the pork in a flameproof/ovenproof dish and bake at 375 degrees, about 10 minutes for rare or 20 minutes for medium well. Remove pork to a platter and let rest 10 minutes. While the tenderloin rests, make the sherry pan sauce, if using. Otherwise, remove twine, carve and serve with pan juices.
Pedro Ximenez sherry pan sauce:
Add one tbsp butter, the shallot, garlic and thyme to the pan juices in the dish you roasted the tenderloins in, and sauté over medium heat, stirring occasionally until shallots are translucent, about 5 minutes. Make sure you scrape up all of the caramelized bits from the cooked pork which are stuck to the pan.
Add the Pedro Ximenez sherry and the sherry vinegar and allow to come to a boil. Continue to boil gently until liquid is reduced by half. Add the chicken stock and reduce by half again until the sauce is syrupy. Reduce to low heat and check the seasoning. Add the last tablespoon of butter, mixing constantly until you have a glossy sauce. Do not boil the sauce after this as the sauce will break.
Spoon sauce over sliced bacon wrapped Iberico tenderloin and serve with your choice of vegetables. Don’t forget the crusty bread and a Spanish Rioja wine!