Combine all the marinade ingredients in a bowl and whisk to combine. Remove 1/2 cup of the marinade and set aside. Refrigerate remaining marinade.
Prepare the pork tenderloins by removing any fat and the silverskin. Sprinkle with salt and pepper and place in a flat dish or ziploc bag. Combine the 1/2 cup of marinade with the 1/2 cup of red wine and pour over the pork. Cover and refrigerate ideally for 2-4 hours, turning occasionally. (*If you're rushed, marinade as long as you can, then cook).
When ready to cook, preheat oven to 400° Using an oven-proof skillet over medium-high heat on the stove top, heat the olive oil and the butter. When the butter is melted, add the pork tenderloins and sear on all sides until well browned.
Transfer pork in skillet to pre-heated oven and cook for about 15 minutes, or until meat reaches 155-160° internal temperature. Transfer pork to a cutting board and tent with foil.
Place skillet on stove-top over medium heat and add the remaining refrigerated marinade to the skillet. Whisk well, scraping up the browned bits on the bottom of the pan. Add the cranberries to the pan and bring to a boil. Reduce heat to medium-low and allow to simmer until sauce is thick and syrupy, about 10 minutes.
Notes
Be sure to read the "Cook's Notes" in the original post, for more tips, options, substitutions and variations for this recipe!