Yam and Turnip Stew with Mini Biscuits

Name: Yam and Turnip Stew with Mini-Biscuits
Ingredients: 2 cups all-purpose flour; 1 teaspoon baking powder; 0.25 cup margarine; 3 tablespoons sunflower seeds; 2 tablespoons grated Parmesan cheese; 0.66666668653488 cup milk, divided; 3 tablespoons vegetable oil; 1 onion, sliced; 2 carrots, chopped; 3 turnips, chopped; 1 small yam, peeled and diced; 2 stalks celery, sliced; 2 cups chopped broccoli; 0.5 teaspoon ground coriander; 0.5 teaspoon dried oregano; 0.5 teaspoon dried basil; salt and ground black pepper to taste; 1 (19 ounce) can diced tomatoes; 1 cup vegetable broth