Guinness Beef Pot Pie

Ingredients (15)

• 2 Tablespoons olive oil
• 1 1/2 lbs stew beef
• 1 yellow onion, chopped
• 3 carrots, peeled and chopped
• 2 celery stalks, chopped
• 2 small russet potatoes, peeled and chopped
• 16 ounces crimini mushrooms, sliced in halves or quarters
• 2 teaspoons minced garlic
• 3 stalks thyme, leaves removed
• 1 stalk rosemary, leaves removed
• 1 1/2 cups beef stock
• 1/2 cup Guinness
• 1 Tablespoon cornstarch mixed with 1 Tablespoon water
• Salt and pepper, to taste
• 2 sheets thawed puff pastry