Preheat oven to 425°.

Heat a large heavy roasting pan over high heat. Sprinkle pork evenly with 1/4 teaspoon salt and 1/4 teaspoon pepper. Add 2 tablespoons oil to pan; swirl to coat. Add pork to pan; cook 3 minutes on each side or until browned. Place pork on a plate (pork will not be cooked through). Reduce heat to medium-high. Add potatoes to pan, cut sides down; cook 2 minutes. Remove pan from heat.

Combine remaining 1/2 teaspoon pepper, remaining 2 tablespoons oil, vinegar, and tomato paste in a small bowl, stirring with a whisk. Combine 2 tablespoons balsamic mixture, thyme, onion, and mushrooms in a bowl, tossing to coat. Add mushroom mixture to pan. Bake at 425° for 25 minutes, stirring after 10 minutes. Arrange pork chops over vegetables; bake 10 minutes or until a thermometer registers 145°. Remove pork from pan. Sprinkle vegetable mixture with remaining 1/4 teaspoon salt. Place 1 cup vegetable mixture on each of 4 plates. Top each serving with 1 pork chop, 2 teaspoons remaining balsamic vinegar mixture, 1 1/2 teaspoons parsley, and 1 tablespoon Gorgonzola cheese.