Step 1

Preheat the oven to 350°F. Lightly spray a 9-inch deep dish pie dish with cooking spray. Fit one pie crust into the dish leaving enough overhang to crimp with the top crust. Set aside.

Step 2

In a medium-size skillet over medium-high heat melt the butter. Cook the green onion just until softened around 1-2 minutes.

Step 3

Add the milk and cream cheese. Cook over medium-heat stirring until the cream cheese has melted., Add the garlic salt, black pepper and ground mustard.

Step 4

Dissolve flour in 3 Tbsp cold milk until dissolved. If needed, add more milk 1 Tbsp at a time. Whisk the flour slurry into the the sauce.. Cook over medium-high stirring constantly until thickened. Once the sauce begins to thicken lower the heat and simmer for 2 minutes.

Step 5

After 2 minutes mix-in 1 1/2 cup shredded cheese. Stir until melted.

Step 6

Remove from the heat and add the chopped chicken and broccoli florets. Mix until combined then pour into the pie shell. Sprinkle the top with the remaining 1/2 cup shredded cheese.

Step 7

Fit the second crust on top. Fold and crimp the edges of the two pie crusts together. Cut 4 slits in the middle of the pie.

Step 8

Whisk together the egg and cold water and brush over the the entire crust.

Step 9

Bake for 40-45 minutes until golden. Rest for 10 minutes before serving.