Return the cooking pot to the stove top and add the olive oil. Heat over medium-high heat. Stir in the onion and carrots and saute until the carrots are tender-crisp, 6 to 7 minutes. Stir in the garlic and cook until softened, about 1 minute. Stir in the remaining 1/2 teaspoon salt, the pepper, chopped rosemary, bean mixture and stock. Bring to a boil, then reduce the heat to low and simmer until the stew is heated through, about 5 minutes.