Preheat a grill. Brush the bread slices with 2 tablespoons olive oil, season with salt and pepper on both sides. Grill the bread on both sides until golden and crisp, remove from heat, cut into 1-inch cubes and put in a large bowl. Heat the remaining 1 tablespoon oil in a large pan over medium heat. Once the oil is hot add the thyme and rosemary sprigs, allow the herbs to infuse the oil. Put the tomatoes in a pan, toss until the skins split and become slightly charred, then put in bowl with bread. Add toasted pine nuts, red onions, balsamic vinegar and season with salt and pepper. Garnish with basil, parsley, and chives, toss together gently and serve.