Melt butter in a large skillet or pot on medium heat, add onions, carrots, celery and garlic. Cook until they start to soften about 3 minutes. Add flour and whisk until combined and cook another minute. Add chicken broth and whisk until combined. Add the potatoes and bring to a low boil, reduce heat and simmer 7-8 minutes to soften potatoes. Add chicken, corn, peas, rosemary, thyme, salt and pepper and cream. Simmer for another 5-6 minutes until it becomes thick and bubbly. Remove from heat and let cool, the sauce will thicken. If you are freezing the pot pies bring the mixture to room temperature before filling the pies and freezing.

Preheat oven to 400 degrees Cut the circles for the bottoms and tops of your pies. Place the bottom crusts in the tins and spoon in the mixture. Then top with the second crust. You should be able to get 5 mini 5" pies out of one box of pie crust. Then seal edges with a fork. Make 3 slits in the middle of the top to let the steam release.

Whisk egg white with 1 tablespoon water brush over top of crust. Bake for 30-35 minutes or until crust is golden brown.