In a small bowl, combine flour, broth, sugar, and soy sauce.
Stir until sugar and flour are dissolved.
In a large skillet or wok over high heat, cook and stir beef 2 to 4 minutes, or until browned.
Stir in broth mixture, ginger, garlic, and broccoli.
Bring to a boil, then reduce heat.
Simmer 5 to 10 minutes, or until sauce thickens.