Boil two cups of water before adding the bouillion cubes, and setting the mix aside
Add the flour, sage, garlic powder and the black pepper in a small bowl, to mix them together and to set it aside as well
Add the butter in a saucepan and put it on a low heat, monitoring it with occasional stirring until the butter has melted
When the butter is completely melted, you add in the flour mix and stir constantly while cooking it until it's colour reaches a golden brown
Gently pour the water and cube mix into the sauce pan while still stirring to prevent lumps
For the finishing touch, turn the heat up to medium and to continue to stir until the mixture resembles a creamy and 'pourable' gravy sauce