Melt the butter in a saucepan set over medium-low heat, then whisk in the flour. Continue whisking until the roux has a nutty fragrance, 2-5 minutes.
8 tablespoons unsalted butter, 1/2 cup plus 2 tablespoons all-purpose flour
Slowly whisk in the chicken stock, then whisk in the milk, Better Than Bouillon, garlic powder, onion powder, poultry seasoning, salt and pepper.
1 3/4 cups low-sodium chicken stock, 3/4 cup whole milk, 2 teaspoons Better Than Bouillon, 1/2 teaspoon garlic powder, 1/2 teaspoon onion powder, 1/4 teaspoon poultry seasoning, 1/2 teaspoon fine sea salt, 1/4 teaspoon ground black pepper
Turn the heat up to medium-high and whisk constantly until the liquid is almost boiling, 5-6 minutes. Once thick, remove from the heat (it will continue to thicken slightly as it cools).
Portion into containers and let cool. Refrigerate for up to one week or store in freezable soup containers such as SouperCubes.