In a liquid measuring cup heat the water over 2 minutes until it is almost boiling and very hot. Crush the bouillon cubes as much as you can and stir them or the powder into the hot water. Whisk well until they have dissolved.
In a saucepan melt the butter over medium high. Add the flour and stir until the flour is fully incorporated and no white streaks remaining.
Slowly whisk in the broth until blended.
Add the garlic powder, onion powder, and black pepper. Bring the mixture to a simmer, and whisk for 2-3 minutes, until it thickens.