Make the rice in a medium sauce pan: Boil 2 cups of water with 1 cup of rice and a dash of salt for 25- 30 minutes.
In a large sauce pan, simmer the cashews, fenugreek, and whole cumin in the cooking oil for 1-2 minutes, until fragrant.
Add the onion and garlic and simmer for another 2 minutes, until the onion is slightly transparent.
Add the spinach - no need to thaw in advance. Add the broth. Cook until fully thawed and wilted - about 4 minutes.
Add all remaining ingredients. Bring to a simmer and let cook, covered, for 25-30 minutes. If too thick, or if it is sticking to the bottom, add more broth as necessary. As it cooks, it will thicken.
Serve the curry over rice.