In a shallow dish combine flour, baking powder and salt. Remove 2 T of flour mixture and set aside for now.

Add beaten egg to a second shallow bowl.

Dip chicken in egg then flour mixture to coat.

In a large, nonstick skillet, heat 2 T oil over medium heat. Add chicken and cook 4-5 minutes, until brown. Turn chicken over and cook until chicken is browned and cooked through. Remove chicken from skillet and set aside (or keep in oven to keep warm).

Return skillet back to medium heat and add butter, onions and mushrooms. Cook a few minutes until browned and soft. Sprinkle the remaining flour mixture over mushrooms and onions and stir. Allow the flour to cook out for 1-2 minutes, stirring. Add milk and soy sauce and stir well. Bring to a bubble and then simmer a few minutes until sauce is thickened. Check for seasoning and add salt/pepper as desired.

Pour mushroom mixture over chicken to serve. Garnish with chopped green onions or parsley if desired.