1. Preheat oven to 350°F. Butter or spray oil a 13x9x2" baking dish and set aside.
2. Melt 1 stick of butter in a large skillet over medium-high heat; add 2 TBL olive oil, onions, carrots and celery. Stir often until just beginning to brown, about 10 minutes. Add to bowl with bread crumbs; stir in herbs, salt, and pepper. Pour broth over bread mixture and toss gently until bread has absorbed liquid.
3. Transfer to prepared casserole dish, cover with foil, and bake about 30 minutes.
4. Uncover, and bake until top is browned and crisp, 10-15 minutes longer.