Step 1Puree the garlic, pimenton, oregano, pepper, a dash of thyme and rosemary, salt, oil and vinegar in a blender container until it is smooth. Place the pork in a non-aluminum bowl and rub the marinade into it. Cover it and refrigerate 24 to 48 hours, turning the meat several times.
Step 2Heat oven to 350 degrees. Drain the meat and place it in a roasting pan. Roast uncovered to an internal temperature of 165 degrees, about 1 hour, depending on the thickness of the meat. If you don't have a thermometer, test the meat after 1 hour by cutting into the center. The meat should be juicy and only slightly pink in the center. If it is still red, roast it another 15 to 20 minutes. Remove the meat from the oven and cover it loosely with foil for 10 minutes before slicing.