Preheat oven to 400F, grease a 9x13 casserole dish.
Meanwhile in a medium bowl add hot water and stuffing. See aside to soak for 5 minutes.
In a large skillet over medium heat melt butter then saute onions until translucent,
Add garlic and continue to saute for 30 seconds.
Add chicken cubes and stir all over until chicken is white.
Sprinkle flour on top and keep stirring until flour disappears.
Add milk and a cup of broth.
Season with oregano, salt and pepper Continue to cook until sauce thickens.
When sauce thickens a bit, turn heat off add frozen vegetables and remaining ½ cup of broth and mix everything well.
Whisk in sour cream.
Pour chicken mixture onto your prepared casserole dish.
Top with stuffing mixture and spread evenly.
Bake for 20 minutes or until top is golden brown.