Pre-heat an outdoor grill to medium high heat. Scrub Potatoes and pat dry. cut into quarters and place in a medium bowl. Cut garlic into 4 pieces, add to bowl along with sprigs of rosemary and thyme. Toss with 2 tablespoons of olive oil and season with salt and pepper. Empty contents of bowl onto a large sheet of aluminum foil, then close the sides up in a pouch. Set pouch on hot grill and roast until Potatoes are tender (about 15-20 minutes). Move package to outer edge of grill to keep warm.

Making the Relish
Bring a small pan filled half way with water to a boil. Core tomatoes and cut a small X on the bottom of each tomato. Gently add tomatoes to boiling water and simmer until tomato skins start to split (about 30 seconds). Transfer tomatoes to a bowl of ice water and let them cool. Drain tomatoes and cut in half, scooping out and discarding seeds. Dice tomatoes and combine with remaining olive oil, vinegar and orange juice. Season tomatoes with salt and pepper to taste, mix well and set aside.