The recipe was a hit in my house. All we really needed to add in the end was a tad bit more salt. If you can't find puffed pastry, maybe try canned biscuits on top when there is about 15 mins left in the baking process.
Mushroom Pot Pie
by Real Simple
4 tablespoons olive oil
1 1/2 pounds mushrooms (such as cremini or button), halved, or quartered if large
4 carrots, cut into 1/2-inch pieces
3 celery stalks, sliced 1/4 inch thick
1 medium onion, chopped
1/2 teaspoon dried thyme
kosher salt and black pepper
1/3 cup all-purpose flour
1 1/2 cups vegetable broth
1 cup frozen peas
1 sheet puff pastry (half a 17.3-ounce package), thawed
Heat oven to 400° F. Heat 2 tablespoons of the oil in a large skillet over medium-high heat. Add the mushrooms, carrots, celery, onion, thyme, ½ teaspoon salt, and ¼ teaspoon pepper. Cook, stirring occasionally, until the vegetables are tender, 12 to 15 minutes. Add the flour and cook, stirring, for 30 seconds. Add the broth and peas; bring to a boil.
Transfer the mushroom mixture into an 8-inch square baking dish. Lay the pastry on top and cut several vents in it. Place the baking dish on a rimmed baking sheet and bake until the crust is golden, 25 to 30 minutes. Let rest 15 minutes before serving.