Beans and Franks Pot Pie

Ingredients

 * 1 tbsp vegetable oil
 * 1 large onion, chopped (1½ cups)
 * 6 cups vegetarian baked beans (2 x 28 oz cans)
 * 6 tofu hot dogs, cut into ½-inch chunks
 * 2 tsp mustard

Cornmeal biscuit topping

 * 1½ cups unbleached all-purpose flour
 * ½ cup fine yellow cornmeal
 * 1½ tbsp sugar
 * 1½ tsp baking powder
 * ½ tsp baking soda
 * 4 tbsp cold unsalted butter, cut into ¼-inch pieces
 * ¾ cup buttermilk

Directions

 * 1) In 4-quart Dutch oven or flameproof casserole, heat oil over medium heat.
 * 2) Add onion and cook, stirring often, until softened, about 8 minutes.
 * 3) Stir in beans, tofu dogs, mustard and salt and pepper to taste.
 * 4) Reduce heat to low and cook, stirring occasionally, while you prepare topping.
 * 5) Preheat oven to 400°F.
 * 6) In medium bowl, mix flour, cornmeal, sugar, baking powder and baking soda.
 * 7) Cut in butter with pastry blender or two knives until mixture resembles coarse crumbs.
 * 8) Make well in dry ingredients.
 * 9) Add buttermilk all at once.
 * 10) Stir just until mixture is blended and dough pulls together.
 * 11) Let dough sit 2 minutes.
 * 12) Dust dough with flour and transfer to floured work surface.
 * 13) Knead 4 or 5 times, then pat into circle as large as the top of Dutch oven.
 * 14) Using sharp knife, cut dough into 2-inch squares.
 * 15) Place dough squares over hot beans.
 * 16) Bake until topping is lightly golden, about 20 minutes.
 * 17) Let cool at least 10 minutes before serving.