Preheat oven to 400°F and lightly grease a 7” x 11” casserole dish.

Melt the butter in a large skillet, and sauté the onions, garlic, sage, and thyme. Simmer for about 5 minutes, or until the butter starts to brown. Be careful not to cook too long, lest you burn the butter!

Gradually whisk in the flour, salt, and pepper. Cook for one minute.

Gradually stir in the broth and milk. Cook over medium heat for about 5 minutes, constantly stirring until the mixture has thickened and is bubbling.

Add in the carrots, celery, and broccoli. Cook until tender, about 5-7 minutes. Then add in the shredded chicken. Pour the mixture into the prepared casserole dish.

On a lightly floured surface, roll out your pie crust dough into a large rectangle. Cut the dough into ¾” wide strips for your lattice topping. Arrange the strips on the top of the filled casserole dish, alternating over and under for a lattice pattern (see picture). Brush the dough with the lightly beaten egg.

Bake for 35-40 minutes, until the pastry is golden brown.