Place seeds in a blender or food processor and process for 30 to 40 seconds, until mixture is a powdery paste. Set aside.
In large saucepan, heat oil over medium high for 4 to 5 minutes. Add beef, stir and fry for 3 to 5 minutes or until browned but not cooked through.
Place tomatoes, onions and chillies in a blender or food processor and process for about 30 seconds or until smooth. Add tomato mixture to beef, reduce heat to medium low and cover. Cook for 40 to 50 minutes or until beef is tender. Season with salt and freshly ground black pepper to taste.
Add passata or tomato cooking sauce, tomato paste, water and prawns then simmer for 10 minutes. Add spinach and ground seeds then continue to simmer 10 minutes more.