Vegetable Pot Pie with Cornbread Topping - ThreeManyCooks

Ingredients

• 1 cup yellow cornmeal, preferably stone-ground, divided
• 1 teaspoon each: baking powder and sugar
• ½ teaspoon salt
• ¼ teaspoon baking soda
• ⅓ cup boiling water
• ¾ cup buttermilk
• 1 large egg, lightly beaten
• 5 tablespoons olive oil, divided
• ⅓ cup all-purpose flour
• ¾ teaspoon dried tarragon, divided
• 1 can (12 ounces) low-fat or regular evaporated milk
• 1½ cups vegetable broth
• Ground black pepper
• ½ pound each: trimmed asparagus, cut into 1-inch lengths, carrots, peeled and sliced, and mushrooms, sliced
• 1 cup frozen peas
• ½ cup thinly sliced scallions, white and green part