Melt butter in a 4 quart saucepan over medium heat.
Add onion and saute until transparent but not brown.
Add flour, blend well and cook 5 to 7 minutes, stirring continuously; do not brown.
Slowly stir 3 cups hot chicken stock into flour mixture and cook over low heat, whisking constantly, until sauce thickens.
Blend in cheese and stir until until cheese melts.
Add tomatoes and undrained vegetables.
Season with pepper, nutmeg, and salt.
Just before serving, stir in hot cream. Dish up in a bread bowl and garnish with popcorn or chopped parsley.