Created by Kchurchill5 on May 14, 2013
Step 1: Onions ... Add the butter and olive oil to a medium saute pan and bring to medium heat. Add the onions, a pinch of salt, mix to combine; then, reduce the heat to medium low heat, and continue to saute for a good 20-25 minutes until golden brown. Don't try to rush this step. You don't want them to burn or brown too quickly. At the start, you don't need to stir them often; but, once they start to caramelize, you will need to stir more often. Once they are done, transfer to a bowl to cool.
Step 2: Pork ... Remove the pork from the refrigerator and lay on a sheet of parchment paper. Cut lengthwise from the top to the bottom (without going all the way through); you are opening it up like a book. Then, cover with plastic wrap, and pound using a meat mallet, to flatten to a thickness of (approximately) 3/8" thick, (this doesn't have to be exact). Lightly season with salt and pepper.
Step 3: Filling ... Add the bread crumbs, cheese, cooled caramelized onions, and rosemary to a small bowl; then, mix to combine.
Step 4: Spread the filling on the tenderloin. You want to leave about a 1/2" border on each end, and one side. The other side - you want to leave about a 2" border. Remember, when you roll the pork, the filling expands. If you don't leave that border, all the filling will "spill" out.
Step 5: Once it is rolled, close using toothpicks or kitchen or butchers twine (which is what I prefer). You can purchase butchers twine at most grocery stores; or often, the butcher will give you some. You can also use any cotton string. Tie the pork in 4-5 places to close up the tenderloin. Then, season the outside of the pork with a mix of salt, pepper, and dried rosemary.
Step 6: Saute ... Sear the tenderloins in a pan (I prefer cast iron or a heavy stainless pan; something that can go from the stove top to the oven), with olive oil and butter on medium high to high heat. Sear until golden brown on each side. You aren't cooking it all the way through; it will finish cooking in the oven.
Step 7: Bake ... If your pan is not oven safe, transfer your tenderloins to a small casserole dish or pan to finish baking in the oven. Otherwise, just transfer your pan to a 400 degree oven (middle shelf), and continue to cook for approximately 8-12 minutes until the internal temperature reaches 145 degrees. For these types of dishes, I do use a thermometer. Once the temp has reached 145 degrees; transfer to a serving platter and cover with foil to rest.
Step 8: Sauce ... Add the wine to the pan you cooked the pork in, with the drippings, and cook 1 minute on medium heat, until 'almost' all the wine has evaporated. Make sure to scrape up the bits on the bottom of the pan, as the wine cooks. Then, add the cranberry sauce, butter, and mix to combine. Cook just a minute to heat through.
Step 9: Serve and ENJOY! ... Once the pork has rested, slice in to thick medallions; and, serve over orzo or mashed potatoes. Sauteed spinach makes a fantastic side dish.