Preheat oven to 325°F. In a large skillet, sauté onion, carrot and potato in olive oil over medium-high heat 5 minutes. Add garlic, herbes de Provence, salt and pepper; sauté another minute. Combine vegetables with bay leaf, beans, tomatoes and vegetable broth in a large, lightly oiled casserole dish. Bake uncovered 20 minutes.