1. Steam the broccoli until tender, about 5 minutes. Remove from the heat and set aside uncovered.
2. Cook the rice according to package directions.
3. While the rice is cooking, heat the oil in a large nonstick skillet over medium-high heat. Add the onion, curry powder, garlic powder, and salt and cook, stirring frequently, until the onion is translucent 5 to 7 minutes.
4. Meanwhile, whisk together the milk and flour in a bowl until well blended.
5. Add the milk mixture, broccoli, and shrimp to the skillet and bring to a simmer stirring constantly. Reduce the heat and continue to simmer and stir gently until the liquid thickens slightly, about 2 minutes.
6. Remove the skillet from the heat and stir in the sour cream.
7. Serve in individual bowls over rice and sprinkle with cashews as desired.