Everyday Food editor Sarah Carey shows you a time-saving way to make classic chicken potpie.
In a large saucepan, melt butter over medium-high. Add onion, celery, and carrots and cook until onion is translucent, about 4 minutes. Add flour and cook, stirring, 1 minute. Gradually add broth, stirring constantly, then bring to a boil. Reduce heat and simmer 5 minutes. Stir in green beans and chicken and season with salt and pepper.
Divide filling among four 8-ounce ramekins. Roll out 1 sheet puff pastry and cut 4 rounds to fit ramekins. Cut a small X in center of each to vent, then place on top of filling. Brush with beaten egg. Bake at 375 degrees until filling is bubbling and crust is golden, 30 to 40 minutes.