Preheat the oven to 375 degrees F. In a medium bowl, toss the whole cherry tomatoes with the olive oil, salt and pepper and place on a rimmed baking sheet in a single layer. Top the tomatoes with the thyme sprigs. Roast the tomatoes for 25-30 minutes, shaking the tray halfway through the cooking time. The tomatoes are done when they start to blister and burst open. Cut or tear the cheese into pieces and arrange the tomatoes with the cheese on a serving platter. Top with a few dollops of the pesto. Garnish with fresh thyme leaves, a sprinkle of sea salt or a drizzle of olive oil.