Heat olive oil in a large skillet over medium high heat and cook celery, carrot and onion, stirring occasionally, for 5 minutes. Add pepper and cook for 2 more minutes. Remove vegetables to a platter and set aside. In the same skillet, add the flour and butter and melt while stirring to form a roux. Slowly whisk in the white wine and chicken stock, a little at a time, until it is completely incorporated and thickened. Return vegetables to the pan and add diced chicken. Cover, bring to a simmer, and poach the chicken for about 7 minutes. Add the asparagus and peas, cover, and cook for 2 more minutes. Stir in peas just until warmed through. Season with tarragon and adjust seasonings as needed. Serve chicken and vegetables poured into the cooked puff pastry shells.
Recipe by Cooking With MicheleĀ® at https://cookingwithmichele.com/2012/12/chicken-a-la-queen/