Preheat the oven to 450°F. Spray a large baking sheet with non-stick cooking spray and set aside.

In a medium saucepan, melt butter over medium heat. Add diced onions and sauté until translucent, about 3-4 minutes.

Add flour, salt, and black pepper. Cook, stirring constantly, until the mixture begins to brown, about 3-4 minutes.

Gradually whisk in chicken broth and milk, stirring constantly to create a smooth sauce.

Cook over medium heat, stirring constantly, until the mixture bubbles and thickens, about 5 minutes. Remove from heat.

Stir in cream cheese, frozen peas and carrots, and diced cooked chicken until well combined.

Unroll pie crusts. Using a 5.5-inch bowl, cut out circles. Gather scraps and re-roll as needed to cut out a total of 8 circles.

Beat egg yolks with water and brush the edges of the pie rounds with the egg wash.

Spoon about 3 tablespoons of filling onto each crust circle. Fold in half to form a crescent and crimp edges to seal.

Brush the top of each hand pie with egg wash and poke a few holes with a fork.

Bake for 10-12 minutes until golden brown and crispy.