Campfire Feijoada

Name: Campfire Feijoada
Ingredients: 2 tablespoons vegetable oil, plus more for brushing; 1 red onion, finely chopped; 2 large garlic cloves, minced; 12 ounces andouille sausage, cut into 1/3-inch-thick rounds; 4 ounces spicy, smoked beef jerky, cut into 1/2-inch squares; 2 1/2 cups plus 2 tablespoons low-sodium beef broth; 1 bay leaf; 1/2 teaspoon dried oregano, crumbled; Two cans black beans with liquid; 1 pound precooked rice; 2 very ripe plantains, peeled and sliced on the diagonal 1/2 inch thick