Homemade Chicken Pot Pie

INGREDIENTS

For the filling:

6 tbsp

unsalted butter (softened)

1/4 cup

all-purpose flour

1 tbsp

cornstarch

1/2 cup

milk

small onion (finely chopped)

medium carrot (peeled and diced)

celery stalk (diced)

1 cup

condensed chicken broth (or 1 cup water plus 2 chicken bouillon cubes)

1/2

medium size russet potato (peeled and diced)

medium size baked chicken breasts (diced (link to the recipe is in the post))

1/2 cup

frozen peas

Salt

Freshly ground black pepper

For the pie pastry:

2 cups

all-purpose flour

1/2 tsp

kosher salt

1 cup

cold unsalted butter, cut into cubes

1/4 cup

ice water

1 tbsp

white vinegar

egg yolk plus 2 tsp milk (mixed well, for brushing)