2½ cups chicken broth
1½ cups milk
¾ cup flour
½ tsp. onion powder
½ tsp. garlic powder
½ tsp. black pepper
1 tsp. salt
½ tsp. parsley
Combine the chicken broth and ½ cup of the milk in a large saucepan. Bring to a low boil.
Meanwhile, in a small bowl, whisk the flour and seasonings into the remaining 1 cup milk until a smooth, thick mixture forms.
Pour the flour and milk mixture into the saucepan with the broth mixture over low heat and stir continuously, whisking as the mixture simmers.
Continue to simmer and stir/whisk until the mixture is smooth and thick, 5-10 minutes. The mixture will thicken a bit as it cools.