Preheat oven to 425°. In a saucepan, melt butter over medium heat. Stir in flour, garlic, salt and pepper until blended. Gradually stir in water, milk and bouillon. Bring to a boil; cook and stir until thickened, 1-2 minutes. Remove from the heat. Stir in chicken and vegetables; set aside. , For pastry, in a large bowl, combine flour and celery seed. Cut in cream cheese and butter until crumbly. Work mixture by hand until dough forms a ball. On a lightly floured surface, roll two-thirds of dough into a 12-in. square. Transfer to an 8-in. square baking dish. Pour filling into crust. Roll remaining dough into 9-in. square; place over filling. Trim, seal and flute edges. Cut slits in pastry. , Bake until crust is golden brown and filling is bubbly, 30-35 minutes.