Wash hands with soap and water.
Reheat the frozen chicken strips according to the package directions. Cut into bite-sized pieces.
Wash counters, cutting board, and knife before handling raw produce. Wash hands with soap and water.
Preheat the oven to 350°F.
Gently rub celery under cold running water. If using fresh onion, scrub onion with a clean vegetable brush under running water.
In a large pan over medium heat, add 1 Tablespoon oil. Then add the onions, celery, and carrots. Cook approximately 5 minutes until the vegetables are tender.
Add the other ¼ cup oil. Once the oil is hot, sprinkle the flour and whisk to combine. Wash hands with soap and water after handling raw flour.
Slowly pour in the chicken stock, whisking constantly to prevent lumps. Then stir in the evaporated milk.
Once the mixture starts to simmer, lower the heat to medium-low and add the chicken, peas, green beans, salt, black pepper, dried thyme, and cayenne pepper. Stir well to combine. Taste and adjust seasonings.
Transfer to a 9 x 13” pan. We used a deep dish pie pan.
Top with the biscuits and brush the biscuits with beaten egg. Wash hands with soap and water after handling raw eggs.
Bake in the oven at 350°F until the internal temperature reaches 165°F on a food thermometer, approximately 20-25 minutes.