Preheat oven to 450°. Lightly spray a rimmed baking sheet with cooking spray.
Sprinkle pork with thyme, salt, and pepper. Wrap 5 bacon slices around each tenderloin, and secure with wooden picks. Place on prepared pan.
Bake for 45 minutes. Meanwhile, in a medium skillet, heat oil over medium-high heat. Add garlic, and cook until golden, 2 to 3 minutes. Add vinegar, and bring to a boil; cook for 2 minutes. Remove from heat, and stir in preserves. Reserve half of mixture in a small bowl; stir ½ cup blackberries into mixture in bowl.
Brush pork with blackberry mixture in skillet. Bake 5 minutes more. Let stand for 10 minutes. Slice tenderloin, and serve with reserved blackberry mixture and remaining 1 cup blackberries.
Recipe by Paula Deen Magazine at https://pauladeenmagazine.com/blackberry-pork-tenderloin-recipe/